Bookofabstracts

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Tableofcontent

Tableofcontent..........................................................................................................................................2Multipointanalysisofcompressivefluctuationsinthefastandslowsolarwind.........5ComparisonofthebowshockandICMEshocks..........................................................................6Differenttypesofforeshockandtheirconnectionwithforeshocktransients................6Acomparisonofionrampsofthebowshockandinterplanetaryshocks:Cluster,THEMISandSpektr-R..............................................................................................................................7HotflowanomalyGeneratedULFWavesintheMagnetosphere.........................................7ThesourceofbackstreamingionsinayoungHotFlowAnomaly........................................8Relativisticelectronsproducedbyforeshockdisturbances...................................................9ReflectedelectronsandelectrostaticwavesobservedbyClusterintheforeshock.....9EffectsofInterplanetaryShocksontheLunarWake..............................................................10Upstreamtransientsandtheirinfluenceonthebowshockandmagnetosheath......10Ontheimportanceofmagnetosheathhigh-speedjets...........................................................11MagneticcloudsintheEarth'smagnetosheath:astatisticalstudy...................................12WhatControlsDaysideReconnection............................................................................................12ElectronDissipationattheDaysideMagnetopausefromMMSMeasurements..........13ClusterObservationsofMagnetopauseReconnectionUnderHighFlow-ShearConditions..................................................................................................................................................14IonLarmorRadiusEffectsnearaReconnectionX-lineattheMagnetopause:THEMISObservationsandSimulationComparison..................................................................................14Clusterobservationsofmagnetopauseasarotationaldiscontinuity:openissuesonMHDreconnectiontests.......................................................................................................................15RecentresultsaboutkineticsofelectronholesinmagnetopausereconnectionobservedbyClusterandMMS...........................................................................................................16TheResponseTimeoftheMagnetopauseReconnectionLocationtochangesintheSolarWind:MMSCaseStudy.............................................................................................................16FluxRopesDynamicsattheSubsolarMagnetopause:MMSObservationsandKineticSimulations................................................................................................................................................17Locatingdaysidemagnetopausereconnectionwithexhaustiondistributions..........18Low-energyionsinthemagnetosphere:Statisticsandconsequences..........................19Oxygenandcoldionsinmagneticreconnection.......................................................................20Kelvin-HelmholtzwavesatEarth'smagnetopause..................................................................21MMSObservationsofMagneticReconnectionAssociatedwithKelvin-HelmholtzWaves...........................................................................................................................................................21Anewviewondriversofmagnetopauselocations..................................................................22ScienceObjectivesforSoftX-rayMissionstotheEarth'sMagnetosphere....................23NewimagingoftheSun-Earthconnection:theSMILEmission..........................................23Theroleofturbulenceinheatingandacceleratingparticles:theTHORmission.....24TheMAARBLEproject:investigatingthepropertiesofelectromagneticwavesandtheirinfluenceonthedynamicevolutionoftheVanAllenbelts.......................................25UnderstandingtheradiationenvironmentintheEarth'sinnermagnetosphere.......26

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InteractionofULFwaveswithdifferentionspecies:pitchangleandphasespacedensityimplications...............................................................................................................................27OntheElegantDynamicsoftheUltra-relativisticVanAllenRadiationBelt:HowULFWaveTransportExplainsanApparentlyDiverseResponsetoSolarWindForcing.27MMSObservationsofEnergeticElectronMicroinjections....................................................28Clusterobservationsofmagnetosonicwavesintheinnermagnetosphere..................29CanEMICtriggeredemissionsbegeneratedoffthemagneticequatorialplane?.......30Finestructureembeddedinwhistlermodechoruswavepackets:observationsofClusterandVanAllenProbesintheinnermagnetosphere..................................................31Theinnermagnetosphereioncomposition................................................................................31ObliqueWhistler-ModeWavesintheEarth'sInnerMagnetosphere...............................32CofelectricradialdiffusioncoefficientofradiationbeltelectronswithinsituelectricfieldmeasurementsbyTHEMIS.......................................................................................................33Plasmasphericplumeanalysisduringthe2013Clustercloseseparationcampaign,augmentedwithVanAllenProbesdataandaplasmapausetestparticlesimulation.........................................................................................................................................................................33Lightningwhistlerstriggeringplasmaspherichiss:multi-spacecraftobservationsandray-tracinganalysis.......................................................................................................................34Erosionandrefillingoftheplasmaspherestudiedbyneuralnetworkbasedthree-dimensionalplasmasphericmodel..................................................................................................35Thegeospaceexplorationproject:ERG........................................................................................36Electricfieldsassociatedwith100skeVelectronenhancementsintheslotregion.36ParticleAccelerationinSolarFlaresandTerrestrialSubstorms.......................................37AnAnalysisofMagneticReconnectionEventsandtheirAssociatedAuroralEnhancements..........................................................................................................................................38Magnetotailfastflowsnearlunarorbit.........................................................................................38MagnetotailCurrentSheetStructurefromClusterandTHEMISObservations...........39StudyingmagneticreconnectionusingtheFOTEmethod:ClusterandMMSresults39ElectricFieldsattheDipolarizationFronts:ClusterandMMSobservations...............40ElectronInjections:AStudyofElectronAccelerationbyMultipleDipolarizingFluxBundlesUsinganAnalyticalModel.................................................................................................40IonHeatingandAnisotropyinMagnetotailReconnectionJets..........................................41Electronfield-alignedanisotropyanddawn-duskmagneticfield:nineyearsofClusterobservationsintheEarthmagnetotail..........................................................................42CLUSTERviewonPSBLionbeamsintheEarth'smagnetotail...........................................42Doesthecross-scaleenergytransportassociatedwithasymmetricgrowthofKelvin-HelmholtzInstabilityexplaintheoriginofplasmasheettemperatureasymmetryofcold-componentions?...........................................................................................................................43Kelvin-Helmholtzinstability:lessonslearnedfromCluster&Themisandwayforward........................................................................................................................................................44ConjugacyofKelvin-HelmoltzInstabilityandPs6duringtheSt.Patrick'sDay2013MagneticStormEvent...........................................................................................................................44CharacterizationofenergeticO+andH+ionsintheplasmasheet..................................45ARTEMISobservationsofterrestrialionosphericmolecularionsattheMoon..........45Plasmasheetdriversofcurrentsandionosphericconductivityeffects.........................46

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DistributionofRegion1and2currentsinthequietandsubstormtimeplasmasheetfromTHEMISobservations.................................................................................................................47AcasestudyontheFACcarriersinthemagnetotailinsubstormtime..........................47Multi-pointstudiesoftheauroraandassociatedcavitybyCluster,andofBBFsandmagnetosheathjetsbyClusterandMMS......................................................................................48Occurrenceofauroralomegabands...............................................................................................49Statisticalpropertiesofsubstormauroralonsetbeads/rays..............................................50Theionosphereasginormousparticledetector.......................................................................50TREx-anASIandRiometernetworkdesignedtotakeTHEMIS-ASI'tothenextlevel.........................................................................................................................................................................51DeterminationofdynamicsofturbulenceupstreamanddownstreamoftheEarth'sBowshock,usingClustermeasurements.....................................................................................52RapidchangesinthesolarwindprotonvelocitydistributionfunctionobservedwithCIS..................................................................................................................................................................52Variabilityoftheelectronpowerspectruminthesolarwind............................................53Turbulenceintheterrestrialforeshock:Multipointobservations....................................53MagneticCurvatureAnalysisonKelvin-HelmholtzWaves:aMHDSimulationStudy.........................................................................................................................................................................54Kelvin-HelmholtzwaveatthesubsolarmagnetopauseboundarylayerunderradialIMF.................................................................................................................................................................55Shapeofthedaysideequatorialmagnetopause........................................................................55Newtoolsformulti-missiondataanalysiswithCluster:SPEDAS,OVTandCSA2.056CorrectingtheRAPIDImagingElectronSpectrometerdatasetforlong-termsensitivitydecrease................................................................................................................................57Statisticalsurveyofquasi-periodicVLFemissionsobservedintheinnermagnetosphereconjugatedwithgeomagneticfieldfluctuationsmeasuredontheground..........................................................................................................................................................57Multipointobservationsoflong-lastingPc4pulsationsinthedaysidemagnetosphere........................................................................................................................................58InfluenceofaguideBYfieldonthemagnetotailcurrentsheetstructureandparticledynamics.....................................................................................................................................................59Substructureswithinadipolarizationfrontrevealedbyhigh-temporalresolutionClusterobservations..............................................................................................................................60Temporalandspatialevolutionofmagnetotaildipolarizationfrontsinthenear-Earthplasmasheet.................................................................................................................................61Comparingandcontrastingdispersionlessinjectionsatgeosynchronousorbitduringasubstormevent......................................................................................................................61IMFdependenceofenergeticoxygenandhydrogeniondistributionsinthenear-Earthplasmasheet.................................................................................................................................62Amulti-satellitesurveyofconvectionintheterrestrialmagnetotail..............................63TheconnectionbetweensmallscalepolarcaparcsandtheLLBL...................................63North-southasymmetriesincoldionoutflowandlobedensity........................................64Solarzenithangledependency,seasonalvariationsandN-Sasymmetryofthepolarwind..............................................................................................................................................................65

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Multipointanalysisofcompressivefluctuationsinthefastandslowsolarwind

O.W.Roberts,1X.Li,2,

Y.Narita3.,C.P.Escoubet1H.Laakso1,4

1ESA/ESTECSCI-SKeplerlaan1,2201

AZNoordwijk,Netherlands2DepartmentofPhysics,Aberystwyth

University,Aberystwyth,SY233BZ,UnitedKingdom.

3SpaceResearchInstitute,AustrianAcademyofSciences,Graz,Austria

4ESA/ESACSCI-S28692VillanuevadelaCanada,Madrid,Spain

Compressibleturbulenceinthesolarwindisatopicofmuchrecentdebate.Tounderstandthevariouscompressivefluctuationsatscalescomparabletoprotoncharacteristiclengthsweusemulti-pointmagneticfieldanddensitydata(derivedfromspacecraftpotential)fromtheClusterspacecraftwhentheywereinundisturbedintervalsofslowandfastsolarwind.Usingthespacecraftpotentialallowsmuchhighertimeresolutionthanistypicallypossiblethanwithparticleinstruments.Thespacecraftpotentialissubjecttoastrongspineffectduetochangesintheilluminatedsurfaceofthespacecraft.Tocorrectforthisanempiricalmodelofthespacecraftchargingisderivedasafunctionofspacecraftangleandisusedtoremovetheeffect.Theapplicationofthemultipointsignalresonatortechniqueisperformedforthefirsttimetoascalartimeserieswithelectrondensityandmagneticfieldfluctuationsalongthebackgroundmagneticfielddirectionbeingusedasinputsinadditiontothetraditionalvectorcomponentsofthemagneticfield.Thisanalysisisperformedontwostreamsofsolarwind,onewhichcanbeclassedasaslowstream,andonewhichcanbeclassedasafaststreamtoinvestigatethedifferenceinthecompressiblecomponentsinthetwotypesofwind.TherecoveredplasmaframefrequenciesOmegafortheincompressiblecomponentshowlowspeedintheplasmaframeconsistentwithpreviousapplicationsofthemethodwhilethecompressiblecomponentsaremorescattered,somewithveryhighphasespeeds.Wediscussthepossiblewaveinterpretationsorcoherentstructureinterpretationstoexplaintheseobservations.Additionallythe

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threedimensionalpowerspectruminwavespaceisinvestigated.

ComparisonofthebowshockandICMEshocks

G.K.Parks1,E.Lee2,S.Y.Fu3,Z.W.Yang4,Y.Liu4,I.Dandouras5,H.Reme5

1:UcBerkeley,Berkeley,CA;2:KyungHeeUniversity,Suwon,Korea;3:PekingUniversity,Beijing,China;4:SpaceWeather,NSSC,Beijing,China;5:IRAPandPaul

SabatierUniversity,Toulouse,FranceCollisionlessshocksareubiquitousinspace.Inadditiontothebowsock,theheliosphereispervadedbytheterminationshockattheheliopause.TherearealsotransientinterplanetaryshocksproducedbysolardisturbancessuchastheCME(CoronalMassEjection)events.TheICMEspeedsrelativetotheambientSWspeedarefasterthanthelocalfastmodespeedoftheSW,hencetheedgescancompressandsteepenintoshockwaves.ICMEshockwavesaretravelingwithspeedsrangingfromafewhundredkm/stomorethanathousandkm/s.ICMEshocksaredifferentfromthebowshockwhichisastandingshockwave.ICMEshocksarealsoofmuchlargerspatialscalesthantheEarth'sbowshock.PreviousstudiesofICMEshocksfromVoyager2haveshownthattheyincludereflectedpopulationsasinthebowshockbuttheycanrepresentasmuchas44%ofthesheathpopulation,muchgreaterthanthe20%observedintheEarth'sbowshock.WehavebegunstudiesofICMEshocksusingClusterdataandinthistalkreportsimilaritiesanddifferencesofEarth'sbowshocktothoseinICMEshocksincludinghowthesolarwindisheatedacrossthesetwotypesofshocks.

Differenttypesofforeshockandtheirconnectionwithforeshocktransients

PrimozKajdic,XochitlBlanco-Cano,DianaRojas-Castillo,NojanOmidi

InstitutodeGeofisica,UNAM;InstitutodeGeofisica,UNAM;SwedishInstituteofSpacePhysics;SolanaScientificIn.c

Whentheanglebetweenthebowshocknormalandtheinterplanetarymagneticfield(IMF)intheupstreamregionislessthan45degrees,theshockiscalledquasi-parallel.Atsuchashockaportionofsolarwindionsisenergizedandreflectedbackupstream.Theinteractionbetweenthesereflectedionsandtheincomingsolarwindresultsinthesocalledforeshockregioninwhichthemagneticfieldishighlyperturbedanddifferentionpopulationsexist.Therearealsotransientstructures,suchasforeshockcavitons,spontaneoushotflowanomaliesandforeshockcompressionalboundaries,populatingpartsoftheforeshock.Recentlywe

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performedamulti-spacecraftanalysisofforeshockobservationsbyThemisandClustermissionsinordertoshowthattwodifferenttypesofforeshockmaybedetectedinthedata.Thereisaglobalforeshockthatformsupstreamofthequasi-parallelsectionofthebow-shockundersteadyorvariableIMF.WhentheIMFchangesitsorientation,theforeshockchangesitslocationwithrespecttothebow-shock.Anothertypeisatravelingforeshockthatformswhenmagneticfluxtubesconnectwiththenominallyquasi-perpendicularsectionofthebow-shockinaquasi-parallelway.TravelingforeshockspropagatealongthebowshocksurfaceandappearinthespacecraftdatadelimitedbyrotationalIMFdiscontinuities.Therelationsoftheforeshockphenomenawithsuchforeshockswillbediscussedandalsotheimplicationsforthedownstreamphenomena,suchasmagnetosheathjets.

Acomparisonofionrampsofthebowshockandinterplanetaryshocks:Cluster,THEMISandSpektr-R

O.Goncharov(1),O.Kruparova(2),J.Safrankova(1),Z.Nemecek(1),L.Prech(1),

andG.N.Zastenker(3)

(1)CharlesUniversity,FacultyofMathematicsandPhysics,Prague,CzechRepublic,(2)InstituteofAtmosphericPhysics,TheCzechAcademyofSciences,Prague,CzechRepublic,(3)SpaceResearchInstituteofRussianAcademyofScience,Moscow,

Russia.CollisionlessshocksplayasignificantroleinthesolarwindinteractionwiththeEarth.Fastforwardshocksdrivenbycoronalmassejectionsorbyinteractionoffastandslowsolarwindstreamscanbeencounteredintheinterplanetaryspace,whereasthebowshockisastandingfastreverseshockformedbyinteractionofthesupersonicsolarwindwiththeEarthmagneticfield.Bothtypesofshocksareresponsibleforatransformationofapartoftheenergyofthedirectedsolarwindmotiontoplasmaheatingandtoaccelerationofreflectedparticlestohighenergies.Theseprocessesarecloselyrelatedtotheshockfrontstructure.Thepapercomparesthestructureoflow-MachnumberfastforwardinterplanetaryshocksregisteredbyWindandACEwithobservationsofbowshockcrossingsobservedbytheCluster,THEMIS,andSpektr-Rspacecraft.Applicationofthehigh-timeresolutiondatafacilitatesfurtherdiscussiononformationmechanismsofbothtypesofshocks.

HotflowanomalyGeneratedULFWavesintheMagnetosphere

L.L.Zhao,H.Zhang,Q.-G.Zong

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PekingUniversity,UniversityofAlaskaFairbanksHotflowanomalies(HFAs)areeventsobservednearplanetarybowshocksthatarecharacterizedbygreatlyheatedsolarwindplasmasandsubstantialflowdeflection.HFAsareuniversalphenomenathathavebeenobservednearthebowshockofEarth,Venus,Mars,andSaturn.Severalstudieshavedemonstratedthattransientphenomenanearthebowshock(suchasHFAsandForeshockBubbles)cangenerateULFwavesintheEarth'smagnetosphere.(Thisisdifferentfromthelow-latitudePc3wavesthataredrivenbyupstreamwavesintheionforeshock.)TheULFwavesgeneratedbytransientphenomenanearthebowshockinbothPc3andPc5rangeshavebeenreported.Inaddition,theremaybeconsiderablevariationbetweenULFwavesresultingfromdifferenttransientfeatures(e.g.,Hartingeretal.[2013]showedmostlycompressionalwaveswhereasEastwoodetal.[2011]showedstandingAlfvenwaves).WereportHFAgeneratedPc3ULFwavesobservedbymultiplespacecraftandgroundstations.TheULFwavesarestandingAlfvenwaves.Thewavepowerofpoloidalmodeisstrongerthanthatoftoroidalmode.ThePc3ULFwaveswereobservedatdawn,noonanddusksectors,indicatingthemagnetosphericresponsetotheHFAisglobal.

ThesourceofbackstreamingionsinayoungHotFlowAnomaly

O.L.Vaisberg,S.D.Shuvalov,A.Yu.Shestakov,Y.M.Golubeva

SpaceResearchInstitute(IKI)WeanalyzeaneventinfrontofthebowshockobservedbyClusterspacecrafton22.02.2006.ThiseventhasmanyattributesofHotFlowAnomalyatearlystageofdevelopmentincludingstrongupstreambeamanddisturbedmagneticprofilewithincreasedmagneticfieldatoneortwosidesasobservedby4Clusterspacecraft.Theanglebetweenthemagneticfieldvectorsattwosidesofthecurrentsheetwas~100.TheminimummagneticfieldmagnitudewithinHFAwas~1nT.TheshockattwosidesoftheHFAwasquasi-perpendicular.UpstreambeamwasobservedontheleadingsideoftheHFA.ParametersandvelocitydistributionsofsolarwindionsandofupstreamionsobservedonC1andC3spacecraftareanalyzedseparatelyinordertotracetheirchangesacrosstheevent.Thegoalofthisanalysiswastogetmoreinformationaboutthesourceofupstreambeam.ThebeamevolvedfromthestartofitsobservationtilltheHFAencounterbeinginitiallyenergeticandnearlymono-energetic.ItsmeanenergycontinuouslydecreasedandenergyspectrumwidenedasHFAapproachedspacecraft.FirstobservationofparticularenergythatdiminishedwithapproachingtheHFAvariedlinearlywithgyro-radiusofions.LowestenergiesinthebeamwereobservedwithinHFAonly.Highestdensityandpressureofupstreambeamarefoundinthecurrentsheetitself.TheenergyspectraofintegratedbeamandtheenergyspectrumofthebeamobservedjustinfrontofHFA

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areverysimilartotheenergyspectrumupstreammagnetosheathionsobservedafterbowshockcrossingat~1hourafterobservationoftheHFA.WesuggestthattheupstreambeamistheresultofthemagnetosheathionsleakagethroughtheregionofHFAcrossingwiththebowshockfront.

Relativisticelectronsproducedbyforeshockdisturbances

LynnB.WilsonIII;DavidG.Sibeck;DrewL.Turner;AdnaneOsmane;DamianoCaprioli;VassilisAngelopoulos

NASAGoddardSpaceFlightCenter;NASAGoddardSpaceFlightCenter;TheAerospaceCorporation;AaltoUniversity;PrincetonUniversity;Universityof

California,LosAngelesForeshockdisturbances--large-scale(~1000kmto>30,000km),solitary(~5--10perday,transient(lasting~10sofsecondstoseveralminutes))structures--generatedbysuprathermal(>100eVto100sofkeV)ionsariseupstreamofEarth'sbowshockformedbythesolarwindcollidingwiththeEarth'smagnetosphere.TheyhaverecentlybeenfoundtoaccelerateionstoenergiesofseveralkeV.Onetypewasfoundtohaveadistinctsuprathermalelectronpopulationwithenergies>70keV,whichwasattributedtoamagnetosphericorigin.AlthoughelectronsinSaturn'shighMachnumber(M>40)bowshockcanbeacceleratedtorelativisticenergies(nearly1000keV),ithashithertobeenthoughtimpossibletoaccelerateelectronsatthemuchweaker(M<20)Earth'sbowshockbeyondafew10sofkeV.Herewereportobservationsofelectronsenergizedbyforeshockdisturbancesfrom10sofeVuptoatleast~300keV.Weobserveasingleisotropicpower-lawfrom100sofeVto100sofkeV,unlikepreviousstudies.Allpreviousobservationsofenergeticforeshockelectronshavebeenattributedtoescapingmagnetosphericparticlesorsolarevents.Weobservenosolaractivityandthesingleisotropicpower-lawcannotbeexplainedbyanymagnetosphericsource.Further,currenttheoriesofionaccelerationinforeshockdisturbancescannotaccountforelectronsacceleratedtotheobservedrelativisticenergies.Theseelectronsareclearlycomingfromthedisturbances,leavinguswithnoexplanationfortheaccelerationmechanism.

ReflectedelectronsandelectrostaticwavesobservedbyClusterintheforeshock

JanSoucek(1),DavidPisa(1),OndrejSantolik(1,2)

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(1)InstituteofAtmosphericPhysicsCAS,Prague,CzechRepublic(2)CharlesUniversity,Prague,CzechRepublic

Theforeshockregionofthesolarwindispopulatedwithelectronsreflectedbythebowshock.Thereflectionprocessandpropagationeffectsformelectronbeamswhichoftendrivetheplasmadistributionunstable.Thepresenceofforeshockbeamsistypicallyidentifiedinspacecraftdatathroughobservationofcharacteristicelectrostaticwavesaroundthelocalplasmafrequency.Directobservationsofthebeamsaremoredifficultduetotheirtransientnatureandlowdensity.Onlyafewexperimentalstudiesonthistopicexist,butthePEACEinstrumentofClustercanconsistentlyobservesomeofthedenserfield-alignedelectronbeamsandthebeamenergycanbederivedfromtheobservations.Atothertimes,aplateauintheelectrondistributionresultingfromthedissipationofthebeambywave-particleinteractionisobserved.Weanalyzedasetofforeshockeventswheredirectbeammeasurementswerepossible.Weinvestigatedadependenceofbeamenergyonthelocationwithintheforeshockandcomparedtheresultswithanexistingmodel.Beamobservationswerecorrelatedwiththequalitativecharacteroftheobservedwavespectrumandforindividualcasestheobservedelectrondistributionswereusedasaninputfordispersionrelationcalculation.

EffectsofInterplanetaryShocksontheLunarWake

XiaoyanZhou,ChrisRussell,VassilisAngelopoulos

UCLAAsanonconductiveobstacleinthesolarwindflow,theMooncreatesaplasmavoidbehinditsbodyintheanti-sunwarddirection.Thisvoid,whichhasalowplasmadensity,hightemperatureandmagneticfieldstrength,iscalledthelunarwake.Therehavebeenmanyobservationsandstudiesofthelunarwake.UsingtheextensivedatasetnowobtainedbyARTEMIS,thispaperstudiestheshockeffectsinthelunarwake.TherehavebeenseveraloccasionsduringwhichoneoftheARTEMISspacecraftwaslocatedinthelunarwakeatthetimeaninterplanetaryshockhittheMoonandcompressedthewake.Wediscusshowtheplasmaandmagneticfieldreactedtotheshockwavebycomparingtheobservationsinsidethewakeandinthenearbysolarwindandbycomparingtheeffectsatdifferentdistancesinthewake.Wealsoinvestigatehowsucheffectsvarywiththeshocknormal,ThetaBn,andtheshockcriticality.

Upstreamtransientsandtheirinfluenceonthebowshockandmagnetosheath

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XochitlBlanco-CanoandPrimozKajdic

InstitutodeGeofisica,UNAM,MexicoCity,MexicoInthistalkwewillpresentpreliminaryresultsoftheGIClusterprojectUpstreamtransientsandtheirinfluenceonthebowshockandmagnetosheath.Ouraimistostudythemaincharacteristicsofupstreamtransients(cavitonsandSHFA),anddiscusshowtheycanmodifythesolarwind,thebowshockstructure,andthemagnetosheath.TheuseofClustermulti-spacecraftcapabilitiespositionedatshortseparationdistanceswillallowustodetermineindetailthe3Dmorphologyofstructuressuchascavitons,anddeterminehowtheyevolveastheyapproachtheshockandinteractwithotherforeshockphenomena.WealsowanttostudyinmoredetailtheformationofSHFA.Otherpointofinterestistodeterminehowthesetransientscancontributetoprocessessuchasshockreformationandshockrippling.

Ontheimportanceofmagnetosheathhigh-speedjets

FerdinandPlaschke,HeliHietala

SpaceResearchInstitute,AustrianAcademyofSciences,Graz,Austria.DepartmentofEarth,Planetary,andSpaceSciences,UniversityofCaliforniaLos

Angeles,CA,USA.Thedaysidemagnetosheathisoftenpermeatedbyhigh-speedjetswhicharetransient,localized,andcoherentenhancementsindynamicpressure.Thesejetsoccurmuchmorefrequentlydownstreamofthequasi-parallelbowshock,i.e.,underquasi-radial(lowconeangle)interplanetarymagneticfield(IMF)conditionsinthesubsolarmagnetosheath.Hence,theyoriginatefromprocessesintheforeshockorattheshockitselfandprovidelong-rangecouplingbetweentheseregionsandthedownstreammagnetopause.Asjetsarecarriersofmass,momentum,andenergy,theconsequencesofthemimpactingthemagnetopausecanbemanifold:Theymaytriggerlocalreconnectionand/orcauselocalized,largeamplitudeindentationsofthemagnetopause.Thesemayresultinsurfacewavesorinner-magnetosphericwaves,maymodifydriftpathsofradiationbeltelectrons,andmayevencauseenhancementsinionosphericconvectionanddisturbancesofthegeomagneticfield,observableonground.Naturally,theconsequenceswillscalewiththesizeofthejets.Scalesizedistributionsarefoundtobewellrepresentedbyexponentialfunctionswithcharacteristicsizesof1.34RE(perpendicular)and0.71RE(paralleltothejetflowdirection),respectively.Therewith,impactratesofjetswithcross-sectionaldiameterslargerthan2REareobtained:Theselargescalejetshitthedaysidemagnetopauseonceevery20minutes,onaverage,andonceevery6minutesunderlowIMFconeangleconditions.Hence,jetsarethemostcommondaysidetransients.

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MagneticcloudsintheEarth'smagnetosheath:astatisticalstudy

L.Turc(1),D.Fontaine(2),C.P.Escoubet(1),E.Kilpua(3)

(1)EuropeanSpaceResearchandTechnologyCentre(ESA/ESTEC),Noordwijk,TheNetherlands

(2)LPP-CNRS-EcolePolytechnique,Palaiseau,France(3)DepartmentofPhysics,UniversityofHelsinki,Helsinki,Finland

Magneticclouds(MCs)arehighlygeoeffectivesolarwindtransients.Intheinterplanetaryspace,theypossessawell-definedmagneticstructure,characterisedbyanenhancedandsmoothlyrotatingmagneticfield.Weexamineherewhethertheirmagneticstructureismodifiedwhentheyencountertheouterregionsofthegeospace,namelythebowshockandthemagnetosheath.SignificantchangesinthemagneticstructureofMCscouldinturnaffectthelevelofgeomagneticactivitytheyinduceinthenear-Earth'sspace.Wepresentheretheresultsofastatisticalstudycovering15yearsofdata,from2000to2014.Weidentify82MCswithsimultaneousobservationsinthesolarwindandinthemagnetosheath.ThemagnetosheathmeasurementsareobtainedfromCluster,Themis,Geotail,Double-StarandInterball-Tail,whilethesolarwinddataareprovidedbyACEorWind.Oneachoftheseevents,werunamagnetosheathmodelinordertorelatethemagnetosheathobservationstothebowshockproperties.For66events,themodelyieldsreliableestimatesofthebowshockparameters.Ourresultsshowastronganti-correlationbetweentheshocknormalangleandthevariationofthemagneticfielddirectionfromthesolarwindtothemagnetosheath.Weinvestigatehowthisvariationisdistributedonthemagneticfieldconeangleandclockangle,anddiscussitsconsequencesforthedifferentmagneticfieldcomponents.WethengointodetailanalyzingtheevolutionoftheBzcomponentfromthesolarwindtothemagnetosheath,becauseofitssalientroleintermsofgeoeffectivity.WefindthatthesignofBzinthemagnetosheathcandifferfromthatinthesolarwind.WeinvestigatetheconditionswhichleadtosuchaBzreversalandshowthatitisgenerallyrelatedtospecificupstreammagneticfieldorientations.

WhatControlsDaysideReconnection

JoeBorovsky

SpaceScienceInstituteContrarytodecadesofacceptedknowledge,theauthorhasarguedthattheelectricfieldofthesolarwindhasnothingtodowiththedaysidereconnectionrate.(Althoughthesolar-windelectricfieldorsomethingsimilarcangetintothemagnetospherepost-reconnectionanddrivegeomagneticactivityinanMHD-generatorfashion.)Todeterminewhatdrivesdaysidereconnection(1)welookat

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theCassak-Shayequationdescribingthetwo-plasmareconnectionrateintermsoflocalplasmaparametersand(2)determinewhatintheupstreamsolarwindcontrolsthoseparameters.FiveparametersappearintheCassak-Shayequation:themagnetic-fieldstrengthinthedaysidemagnetosphereandinthesheathB_magandB_sh,thenumberdensityinthedaysidemagnetosphereandinthesheathn_magandn_sh,andthemagneticclockangle'Clock'.B_magiscontrolledbytherampressureofthesolarwindn_swv_sw^2,B_shiscontrolledbytherampressureandthemagnetosheathplasma-betan_swv_sw^2andbeta_sh,andbeta_shiscontrolledbythesolar-windMachnumberM_A,n_shiscontrolledbyn_sw,andClockisthesolarwindClock.So,n_swv_sw^2,M_A,n_sw,n_mag,andClockcontroldaysidereconnection.Usingdifferingapproximations,aseriesof'R'functionsdescribingthereconnectionratehavebeenderived,thesimplestofwhich(whichignoresn_sh)isR_quick=sin^2(Clock/2)n_sw^1/2v_sw^2M_A^-1.35[1+680M_A^-3.30]^-1/4.Inthehigh-Mach-numberandlow-Mach-numberlimits,Rquicklookslikevariantsofthesolarwindelectricfield.Theoldlogicwas:thesolar-windelectricfieldcontrolstheelectricfieldinthedaysidereconnectionlinewhichcontrolsthereconnectionrate.Amore-accuratelogicis:theelectricfieldinthedaysidereconnectionlineiscontrolledbytherateofreconnection.

ElectronDissipationattheDaysideMagnetopausefromMMSMeasurements

J.L.Burch(1),J.M.Webster(2),K.J.Genestreti(3),T.D.Phan(4),R.B.Torbert(5),B.L.Giles(6),M.Hesse(6),R.E.Ergun(7),L.-J.Chen(8),S.Wang(8)

(1)SouthwestResearchInstitute,(2)RiceUniversity,(3)IWFGraz,(4)UCBerkeley,(5)UniversityofNewHampshire,(6)NASA-GSFC,(7)UniversityofColoradoLASP,

(8)UniversityofMarylandDuringitsfirstoftwoscansofthedaysidemagnetopause,MagnetosphericMultiscale(MMS)encounteredtenelectrondissipationregions(EDRs).Withspacecraftseparationsbetween10and40km,thefourspacecraftallpassedthroughorveryclosetoeachEDRbutnotallsimulataneously.Fortheseconddaysidescantheseparationhasbeenreducedto7kmtoprovideabetterchanceofallfourspacecraftbeinginanEDRsimultaneously.SuchconjunctionsbecomeveryimportantforanalyzingmagneticandelectricfieldsandelectrondistributionfunctionstodeterminetheimportanceofpossiblesourcesofthereconnectionelectricfieldinthegeneralizedOhm'sLaw.Thispaperpresentselectron-scaledissipationderivedfrommeasuredout-of-planecurrentsandreconnectionelectricfieldsforEDRswithvariousmagneticguide-fieldvalues.Disspationisobservedatbothin-planemagneticnullsandflowstagnationpointswiththeirrelativestrengthsvaryingwithguidefield.Forexample,verysmallguidefieldsleadtodissipationconcentratedattheflowstagnationpointwhileguidefieldsnearunityshowdissipationinbothregions.Thedissipationatthein-planemagneticnullappearstoresultfromout-of-planecurrentsflowingalongtheguidefield,whichisnot

14

significantforverysmallguidefield.InadditiontotheEDReventsfromthefirstdaysidescan,anyEDRsobservedinthesecondscan,beginninginOctober2016,willalsobepresented.

ClusterObservationsofMagnetopauseReconnectionUnderHighFlow-ShearConditions

F.D.Wilder(1),S.Eriksson(1),K.J.Trattner(1),P.A.Cassak(2),C.E.Doss(2),C.M.

Komar(3),S.A.Fuselier(4),B.Lybekk(5)

(1)LaboratoryforAtmosphericandSpacePhysics,UniversityofColoradoBoulder,(2)WestVirginiaUniversity,(3)NASAGSFC,(4)SouthwestResearchInstitute,(5)

UniversityofOsloWhentheIMFisnorthward,reconnectionoccursineachhemisphereonlobefieldlines,polewardofthecusp.WehaveidentifiedacasewheretheClusterspacecraftcrossedthemagnetopauseandencounteredatailward-retreatingx-line.Thex-lineisidentifiedbytheencounterofbothatailwardandsunwardjet,aswellasHallmagneticfieldsignaturesintheout-of-planedirection.Usingtwospacecraftweareabletoresolvethevelocityofthestructure,whichmovesnearthemagnetosheathspeed.TheresultsarecomparedwiththeoryandPICsimulations,andthespeedofthex-lineisfoundtobeconsistentwithasymmetricreconnectiontheory.Additionally,weobserveion-distributionfunctionswithcounter-streamingpopulations,suggestingthatasecondx-lineformedsunwardoftheoriginalone,leadingtoamagneticisland.

IonLarmorRadiusEffectsnearaReconnectionX-lineattheMagnetopause:THEMISObservationsandSimulationComparison

T.D.Phan,M.A.Shay,C.C.Haggerty,J.T.Gosling,J.P.Eastwood,M.Fujimoto,K.

Malakit,F.S.Mozer,P.A.Cassak,M.Oieroset,andV.Angelopoulos

UCBerkeley,UofDelaware,UofColorado,ImperialCollege,ISAS/JAXA,MahidolUniversity,WestVirginiaUniversity,UCLA

WereportaTHEMIS-Dspacecraftcrossingofamagnetopausereconnectionexhaust~9ionskindepths(di)downstreamofanX-line.Thecrossingwascharacterizedbyionjettingatspeedssubstantiallybelowthepredictedreconnectionoutflowspeed.InthemagnetosphericinflowregionTHEMISdetected(a)penetrationofmagnetosheathionsandtheresultingflowsperpendiculartothereconnectionplane,(b)ionoutflowextendingintothemagnetosphere,and(c)

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enhancedelectronparalleltemperature.Comparisonwithasimulationsuggeststhatthesesignaturesareassociatedwiththegyrationofmagnetosheathionsontomagnetosphericfieldlinesduetotheshiftoftheflowstagnation-pointtowardthelow-densitymagnetosphere.Ourobservationsindicatethattheseeffects,~2-3diinwidth,extendatleast9didownstreamoftheX-line.Thedetectionofthesesignaturescouldindicatelarge-scaleproximityoftheX-line,butdonotimplythatthespacecraftwasupstreamoftheelectrondiffusionregion.

Clusterobservationsofmagnetopauseasarotationaldiscontinuity:openissuesonMHDreconnectiontests

A.Blagau(1),G.Paschmann(2),B.Klecker(2),andO.Marghitu(1)

(1)InstituteforSpaceSciences,Bucharest,Romania

(2)Max-PlanckInstituteforExtraterrestrialPhysics,Garching,GermanyWhenmagneticreconnectionisongoing,themagnetopause(MP)behaveslikearotationaldiscontinuity(RD)outsidethereconnectionregion.Within-situsatellitedata,theRDcharacteroftheMPisusuallycheckedbycarryingouttheWalentest,predictingthattheplasmavelocityobservedinthedeHoffmann-TellerframeequalsthelocalAlfvenvelocity.Anotherrelation,relyingonthesameMHDconservationlaws,connectsthevariationinplasmamassdensity,rho,tovariationsinthepressureanisotropyfactor,alpha,sothatrho(1-alpha)isconstant.WhiletheWalenrelationhasbecomeastandardtoolforclassifyingMPcrossingsasRDs,therho(1-alpha)=const.conditionhasneverbeendirectlyverifiedatthesametime,largelyduetoproblemswithdeterminingrhowhennoioncompositionmeasurementswereavailable.WeexploittheavailabilityofhightimeresolutioncompositionmeasurementsonClustertodirectlytesttherelationforseveralMPcrossings,identifiedasRDsfromapplicationoftheWalenrelationtomeasurementsofplasmaionsandmagneticfieldbytheCISandFGMinstruments,respectively.Wefindthatinneithercasetherelationisfulfilled.ThroughcomparisonsofthemeasurediondensitieswithsimultaneouslymeasuredtotalelectrondensitiesbytheWHISPERinstrumentwewereabletoexcludethepossibilitythationpopulationshiddentotheCISinstrumentbecauseoftheirverylowenergiescouldhavechangedrhotomatchtherho(1-alpha)=const.condition.WealsoexcludedthepossibilitythatenergeticionsabovetheCISenergyrangecouldhavesufficientlychangedthetruealpha.Itthusappearsthattherho(1-alpha)=const.condition,forreasonsnotpresentlyunderstood,isnotvalidforthekindofRD-likestructuresweobserved.Anotheropenissuerelatestothefactthat,inexperimentalcontext,theplasmaflowvelocityistypicallyjust0.6-0.8oftheAlfvenvelocity.Thisdiscrepancymightoriginateinanumberofsimplifyingassumptions,twoofwhichareexaminedinthe

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presentation.Onesimplificationconsidersalltheionsasprotons,anapproximationusuallyjustifiedbythelargeprevalenceoftheprotonsintheMPenvironment.AClustereventveryrichinOxygenionsisusedtochecktheinfluenceofthisminorionspeciesbyemployingaformulabasedonthecenter-of-massmomentsinsteadoftheprotonmoments.AnothersimplifyingassumptionistotestfortheWalenrelationbasedontheionvelocities,althoughthemagneticfieldismorecloselytiedtotheelectronvelocities,whichdifferfromtheionvelocitieswheneverelectriccurrentsareflowing.ForaClustereventwithsmallinter-spacecraftseparationdistance,wehaveinferredtheelectronvelocitiesfromthemeasuredcurrentsandionvelocities,andperformedtheWalentestwiththeelectronvelocities.Althoughinbothcasesthecorrectedformulasbroughtanimprovementintheresult,thepredictedvaluesfortheplasmaflowvelocityremainsbelowtheidealvalueoflocalAlfvenvelocity.

RecentresultsaboutkineticsofelectronholesinmagnetopausereconnectionobservedbyClusterandMMS

D.B.Graham,Yu.V.Khotyaintsev,A.Vaivads,M.Andre,+MMSteam

SwedishInstituteofSpacePhysics,Uppsala,Sweden

Electronholes(EHs)arecharacterizedbylocalizedbipolarelectricfieldsparalleltothemagneticfield.EHsarefrequentlyobservedatthemagnetopause,andareoftenassociatedwithmagneticreconnection.TheunstableelectrondistributionsproducedbymagneticreconnectionprovideasourceofEHs.Inparticular,EHsaregeneratedintheseparatrixregionsofasymmetricreconnection,wherelargeelectronflowsareobserved.WeinvestigatethepropertiesofEHsassociatedwithmagneticreconnectionusingClusterandtheMagnetosphericMultiscale(MMS)mission.Usingthesespacecraftweareabletocharacterizethepropertiesofthewaves,suchasspeed,lengthscale,andwavepotential.WeobserveEHswithdistinctspeeds,indicatingthatmultipleinstabilitiescanoccurduringmagneticreconnection.Thissuggeststhatthewavescancoupledifferentelectronpopulationsandelectronswithions,heatingtheplasmaandcontributingtoanomalousresistivity.WediscusstheeffectsofEHsonmagneticreconnectionatthemagnetopause.

TheResponseTimeoftheMagnetopauseReconnectionLocationtochangesintheSolarWind:MMSCaseStudy

K.J.Trattner,J.Burch,R.Ergun,S.A.Fuselier,R.G.Gomez,W.Lewis,B.Mauk,S.M.

Petrinec,C.J.Pollock,T.D.Phan,F.D.WilderandD.T.Young

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1LaboratoryforAtmosphericandSpacePhysics,UniversityofColorado,Boulder,Colorado,USA

2SouthwestResearchInstitute,SanAntonio,Texas,USA

3AppliedPhysicsLaboratory,JohnHopkinsUniversity,Maryland,USA

4NASA/GSFC,Maryland,USA,

5LockheedMartinATC,PaloAlto,USA,

6UniversityofCalifornia,Berkeley,USA

ReconnectionattheEarthsmagnetopauseisthemechanismbywhichmagneticfieldsindifferentregionschangetopologytocreateopenmagneticfieldlinesthatallowenergy,massandmomentumtoflowintothemagnetosphere.ItistheprimarysciencegoaloftherecentlylaunchedMMSmissiontounlockthemechanismofmagneticreconnectionwithanovelsuiteofplasmaandfieldinstruments.ThisstudywillinvestigateseveralmagnetopausecrossingsinthegeneralvicinityofthemagnetopausereconnectionlocationonSeptember19,2015.ThesecrossingsoccurredduringrotationsoftheIMFandareusedtodeterminetheresponsetimeofthereconnectionlocationstosuchchanges.ThestudyshowsthatthereconnectionlocationexhibitsatendencytoremainatitscurrentlocationdespitesignificantrotationsintheIMFandrespondsonlyminuteslatertochangesintheIMF

FluxRopesDynamicsattheSubsolarMagnetopause:MMSObservationsandKineticSimulations

MengZhou1,JeanBerchem1,MostafaEl-Alaoui1,RaymondJWalker2,Giovanni

Lapenta3,EmanueleCazzola3,DavidSchriver1,RobertLRichard1,HaomingLiang1,MelvynLGoldstein4,XiaohuaDeng5,YePang5,ChristopherTRussell2,RobertJStrangeway2,CongZhao2,WilliamRPaterson4,BarbaraLGiles4,CraigJPollock4,BenoitLavraud6,Per-ArneLindqvist7,GöranMarklund7,YuriVKhotyaintsev8,

RobertEErgun9,RoyBTorbert10,JamesLBurch111DepartmentofPhysicsandAstronomy,UCLA,LosAngeles,California,USA2DepartmentofEarth,PlanetaryandSpaceSciences,UCLA,LosAngeles,CA,USA3CentreforPlasmaAstrophysics,DepartmentofMathematics,KatholiekeUniversiteit,Leuven,Belgium4NASA,GoddardSpaceFlightCenter,Greenbelt,Maryland,USA5NanchangUniversity,Nanchang,P.R.China6IRAP,Toulouse,France7RoyalInstituteofTechnology,Stockholm,Sweden

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8SwedishInstituteofSpacePhysics,Uppsala,Sweden9UniversityofColoradoLASP,Boulder,Colorado,USA10UniversityofNewHampshire,Durham,NewHampshire,USA11SouthwestResearchInstitute,SanAntonioTX,USAItisnowwellacceptedthatfluxropesareproducedbymagneticreconnectionandplayacrucialroleinthedynamicsofthereconnectionprocess.Sometimes,multiplefluxropescanbeproduced,whichcancoalescesporadicallyintolargerropes,releasinglargeamountofenergy.Inthispresentation,wereportoneofthefirstin-situobservationsofthecoalescenceofmacroscopicfluxropesbytheMultiscaleMagnetospheric(MMS)mission.Guidedbyresultsof2-Dkineticsimulationsweidentifiedthemergingoftwolarge-scalefluxropeswithsizesof~1REatthesubsolarmagnetopause.ThecoalescenceprocesswascharacterizedbytheoccurrenceofaquadrupolarsignatureinthenormalcomponentofmagneticfieldmeasuredbytheMMSspacecraftwhentheywereinthereconnectionexhaustregionaftercrossingthemagnetopause.Theinnerbipolarfieldwasweakerthantheouterfieldindicatingthatmagneticenergyhadbeendissipatedbythetwomergingfluxropes.Thereconnectingcurrentsheetbetweenthetwofluxropesischaracterizedbyintensecurrentthatwasmainlycarriedbyelectrons,andalargeguidefield.Anelectrondiffusionregionembeddedwithinthecurrentsheetwasmarkedbyanintenseparallelelectricfield,leadingtosignificantenergydissipationinthatlayer.Theenhancementofelectron-drivenwaves(e.g.,electromagneticwhistlerandelectroncyclotronharmonicwaves)observedinthevicinityofthecurrentsheetsuggeststhatthecoalescenceinvolvesmulti-scaleprocesses.

Locatingdaysidemagnetopausereconnectionwithexhaustiondistributions

JeffreyBroll(1,2),StephenFuselier(2,1),KarlheinzTrattner(3)

(1)UniversityofTexasatSanAntonio(2)SouthwestResearchInstitute

(3)LaboratoryforAtmosphericandSpacePhysics,UniversityofColoradoBoulderMagneticreconnectionatEarth'sdaysidemagnetopauseisessentialtomagnetosphericdynamics.Determiningwherereconnectiontakesplaceisimportanttounderstandingtheprocessesinvolved,andmanyquestionsaboutreconnectionlocationremainunanswered.WepresentamethodforlocatingmagneticreconnectionatEarth'sdaysidemagnetopauseundersouthwardIMFconditionsusingonlyionvelocitydistributionmeasurements.Particle-in-cellsimulationsbasedonClustermagnetopausecrossingsproduceionvelocitydistributionsthatwepropagatethroughamodelmagnetosphere,allowingustocalculatethefield-aligneddistancebetweenanexhaustobservationanditsassociatedreconnectionlocation.WedemonstratethisprocedureandcompareourresultswiththoseoftheMaximumMagneticShearModel;wefindgoodagreement

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withitsresults,andshowthatwhenourmethodisapplicableitproducesmorepreciselocationsthantheMaximumShearModel.

Low-energyionsinthemagnetosphere:Statisticsandconsequences

M.Andre(1),W.Li(1),S.Toledo-Redondo(2),Yu.V.Khotyaintsev(1),A.Vaivads(1),D.B.Graham(1),C.Norgren(1,3),J.Burch(4),P.-A.Lindqvist(5),G.Marklund(5),R.Ergun(6),R.Torbert(4,7),W.Magnes(8),C.T.Russell(9),B.Giles(10),T.E.Moore(19),M.O.Chandler(11),C.Pollock(10),D.T.Young(4),L.A.Avanov(10),J.

C.Dorelli(10),D.J.Gershman(9,12),W.R.Paterson(10),B.Lavraud(13,14),Y.Saito(15),A.I.

Eriksson(1),andK.Li(16)

(1)SwedishInstituteofSpacePhysics,Uppsala,Sweden,(2)EuropeanSpaceAgencyESAC,Madrid,Spain,

(3)DepartmentofPhysicsandAstronomy,UppsalaUniversity,Uppsala,Sweden,(4)SouthwestResearchInstitute,SanAntonio,Texas,USA,

(5)\tKTH,Stockholm,Sweden,(6)LASP,UniversityofColoradoBoulder,Boulder,Colorado,USA,(7)UniversityofNewHampshire,Durham,NewHampshire,USA,

(8)SpaceResearchInstitute,AustrianAcademyofScience,Graz,Austria,(9)DepartmentofEarthandSpaceSciences,UCLA,LosAngeles,California,USA,

(10)NASAGoddardSpaceFlightCenter,Greenbelt,Maryland,USA,(11)NASAMarshallSpaceFlightCenter,Huntsville,Alabama,USA,

(12)DepartmentofAstronomy,UniversityofMaryland,CollegePark,Maryland,USA,(13)InstitutdeRechercheenAstrophysiqueetPlanétologie,Universitéde

Toulouse,Toulouse,France,(14)CentreNationaldelaRechercheScientifique,UMR5277,Toulouse,France,

(15)\tInstituteofSpaceandAstronauticalScience,JAXA,Japan,(16)Max-Planck-InstituteforSolarSystemResearch,Göttingen,Germany

MagnetosphericionswithenergieslessthantensofeVoriginatefromtheionosphere.Thelowenergyindicatestheoriginoftheplasmabutalsoseverelycomplicatesdetectionofthepositiveionsonboardsunlitspacecraftathigheraltitudes,whichoftenbecomepositivelychargedtoseveraltensofvolts.Wediscusssomemethodstoobservelow-energyions,includingatechniquebasedonthedetectionofthewakebehindachargedspacecraftinasupersonicflow.Low-energyionstypicallydominatethedensityandfluxinlargeregionsoftheTerrestrialmagnetosphere,alsoathighaltitudes.Thisistruebothonthenightsideandthe

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dayside,duringallpartsofthesolarcycle.Thelossofthisinitiallylow-energyplasmatothesolarwindisoneoftheprimarypathwaysforatmosphericescape.Includinglow-energyionsinmodelsofthemagnetospherewilldecreasetheAlfvenspeed.Low-energyionswillalsochangethestructureofmagneticreconnectionseparatricesanddiffusionregionsatthemagnetopause.Low-energyionsarecommonjustinsidethemagnetopause.Duringreconnectionevents,theselow-energyionsremainmagnetizeddowntosmallerlength-scalesthanthehot(keV)magnetosphericions,introducinganewscale.Whenmagnetizedlow-energyionsarepresent,theHallcurrentscarriedbyelectronscanbepartiallycancelledbytheseions.Theelectronsandthemagnetizedlow-energyionsExBdrifttogether.ThiswillreducetheHallcurrent.AmixtureoflengthsscalescausedbyamixtureofiontemperatureshassignificanteffectsontheHallphysicsofmagneticreconnection.

Oxygenandcoldionsinmagneticreconnection

ShanWang,LynnM.Kistler,ChristopherG.Mouikis,andLi-JenChen

UniversityofMaryland,CollegeParkNASAGoddardSpaceFlightCenterUniversityofNewHampshire

MagneticreconnectionoccurswitharateproportionaltotheinflowAlfvenspeed.IntheEarthmagnetosphere,oxygenionsarepresentnearthereconnectionsiteatmagnetopauseandmagnetotail;coldionswithlowertemperaturesthanringcurrentpopulationscouldalsobeinvolvedinmagnetopausereconnection.Suchadditionalionpopulationsarelikelytoprovidemassloadingandaffectthereconnectionrate.Withdifferentthermalgyro-radii,thepresenceofoxygenandcoldionsintroduceadditionalscalesofreconnectiondiffusionregions.ByanalyzingvelocitydistributionfunctionsobservedbyClusterduringmagnetopausereconnection,wewillshowthathotprotonandoxygenionsfromthemagnetospherejointhereconnectionoutflowthroughademagnetization-pickupprocess.Finitegyro-radiuseffectdeterminesthepenetrationdepthoftheseionstothemagnetosheathsideofthecurrentsheet.Coldionsarelikelytoexperienceanon-adiabaticmotionclosetotheX-line,butifcrossingtheseparatrixdownstream,theyconvectwiththemagneticfieldadiabatically.Observedmassdensitiesfromoxygenandcoldionsduringmagnetopausereconnectionarefoundtobeuptoabout30percent,andmeasuredreconnectionratescloselyfollowtheCassak-Shayformulaprediction.Inordertoprovideanup-to-dateintroduction,wewillreviewrecentprogressesinunderstandingoxygenandcoldionbehaviorsinsimulationsandMMSobservations.Potentialrolesofthesepopulationsinexcitinganddissipatingwavesandinstabilitiesduringreconnectionwillbediscussed.

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Kelvin-HelmholtzwavesatEarth'smagnetopause

ShivaKavosi,Joachim(Jimmy)RaederandHarlanSpence

SpaceScienceCenter,UniversityofNewHampshireMagneticreconnectionisbelievedtobethedominantprocessbywhichsolarwindplasmaentersthemagnetosphere.However,forperiodsofnorthwardinterplanetarymagneticfield(IMF)reconnectionislesslikelyatthedaysidemagnetopause,andKelvin-Helmholtz(KH)wavesmaybeimportantagentsforplasmaentryandfortheexcitationofultra-low-frequency(ULF)waves.TherelativeimportanceofKHwavesiscontroversialbecausenostatisticaldataontheiroccurrencefrequencyexists.Ouranalysis,using7yearsofinsitudatafromtheNASATHEMISmission,hasshownthatKHwavesattheEarth'smagnetopauseareubiquitousandarepresentapproximately19%ofthetimeregardlessofthesolarwindconditions.TheoccurrencerateincreaseswiththeIMFconeangleandmaximizesatzeroclockangleatabout35%fornearnorthwardIMF,andabout10%undersouthwardIMFconditions.AlthoughtheoccurrencerateundersouthwardIMFissignificantlyhigherthanpreviouslydetected,itisstillapproximatelyfourtimeslessthantheoccurrencerateundernorthwardIMF.ThepreviousstudysuggestedthattheirregularandtemporallyintermittentstructureofKHwavesduetodynamicallyactivesubsolarbehaviorundersouthwardIMFconditionmayexplainthepreferentialinsitudetectionofKHwavesundernorthwardIMF.ThisexplanationisalsoconsistentwiththeKHwavesundersouthwardIMFinourdatabase.Toeffectivelyisolatethesedifferences,weperformedOpenGGCMglobalsimulationsforbothconstantidealizedsolarwindandaTHEMISeventandthesimulationresultsshowthattheKHwavesundersouthwardIMFareirregular,higherfrequency,andpolychromaticincomparedtonorthwardIMF.

MMSObservationsofMagneticReconnectionAssociatedwithKelvin-HelmholtzWaves

S.Eriksson(1),B.Lavraud(2,3),F.D.Wilder(1),J.E.Stawarz(1,12),B.L.Giles(4),J.L.Burch(5),W.Baumjohann(6),R.E.Ergun(1),P.-A.Lindqvist(7),W.Magnes(6),C.J.Pollock(4),C.T.Russell(8),Y.Saito(9),R.J.Strangeway(8),R.B.Torbert(10),D.J.Gershman(4),Yu.V.Khotyaintsev(11),J.C.Dorelli(4),S.J.Schwartz(1,12),L.Avanov(4),E.Grimes(8),Y.Vernisse(2,3),A.P.Sturner(1),T.D.Phan(13),G.T.

Marklund(7),T.E.Moore(4),W.R.Paterson(4),andK.A.Goodrich(1)

1LaboratoryforAtmosphericandSpacePhysics,UniversityofColoradoBoulder,Boulder,Colorado,USA,

2InstitutdeRechercheenAstrophysiqueetPlanetologie,UniversitedeToulouse,Toulouse,France,

3CentreNationaldelaRechercheScientifique,UMR5277,Toulouse,France,

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4NASAGoddardSpaceFlightCenter,Greenbelt,Maryland,USA,5SouthwestResearchInstitute,SanAntonio,Texas,USA,

6SpaceResearchInstitute,AustrianAcademyofSciences,Graz,Austria,7RoyalInstituteofTechnology,Stockholm,Sweden,

8InstituteofGeophysicsandPlanetaryPhysics,andDepartmentofEarth,Planetary,andSpaceSciences,UniversityofCalifornia,LosAngeles,California,USA,9InstituteforSpaceandAstronauticalScience,Sagamihara,Japan,

10PhysicsDepartmentandSpaceScienceCenter,UniversityofNewHampshire,Durham,New

Hampshire,USA,11SwedishInstituteofSpacePhysics,Uppsala,Sweden,

12BlackettLaboratory,ImperialCollegeLondon,London,UK,13SpaceSciencesLaboratory,UniversityofCalifornia,Berkeley,California,USA

ThefourMagnetosphericMultiscale(MMS)spacecraftrecordedthefirstdirectevidenceofreconnectionexhaustsassociatedwithKelvin-Helmholtz(KH)wavesatthedusksidemagnetopauseon8September2015whichallowsforlocalmassandenergytransportacrosstheflankmagnetopause.Pressureanisotropy-weightedWalenanalysesconfirmedin-planeexhaustsacross22of42KH-relatedtrailingmagnetopausecurrentsheets(CSs).Twenty-onejetswereobservedbyallspacecraft,withsmallvariationsinionvelocityamongthespacecraft,alongthesamesunwardorantisunwarddirectionwithnearlyequalprobability.OneexhaustwasonlyobservedbytheMMS-1,2pair,whileMMS-3,4traversedanarrowCS(1.5ioninertiallength)inthevicinityofanelectrondiffusionregion.Theexhaustswerelocally2-DplanarinnatureasMMS-1,2observedalmostidenticalsignaturesseparatedalongtheguide-field.AsymmetricmagneticandelectricHallfieldsarereportedinagreementwithastrongguide-fieldandaweakplasmadensityasymmetryacrossthemagnetopauseCS.

Anewviewondriversofmagnetopauselocations

Z.Nemecek(1),J.Safrankova(1),J.Simunek(2),J.-H.Shue(3),andA.A.Samsonov(4)

(1)CharlesUniversity,FacultyofMathematicsandPhysics,Prague,CzechRepublic,(2)InstituteofAtmosphericPhysics,TheCzechAcademyofSciences,Prague,CzechRepublic,(3)NationalCentralUniversity,Jhongli,Taiwan,(4)St.PetersburgState

University,St.Petersburg,RussiaThesolarwinddynamicpressureistheprincipalfactorcontrollingthemagnetopauselocation.Theirmutualrelationisusuallyconsideredinapower-lawformandsuggestedindicesvaryfrom-1/4.8to-1/6.6inparticularmagnetopausemodels.ThepaperanalyzesabouttenthousandsofTHEMISdaysidemagnetopause

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crossingsobservedinabroadrangeofupstreampressures(0.2-20nPa)anddiscussestherelationshipbetweenthedynamicpressureandmagnetopausestand-offdistanceandflaringangle.Wefoundthat(1)thepower-lawformprovidesthebestdescriptionofvariationsofthestand-offdistancewithupstreampressureforafullsetofcrossingsaswellasforsubsetsconstrainedbyasignoftheinterplanetarymagneticfield(IMF)verticalcomponent,IMFconeangle,andsolarwindspeed;(2)themostappropriatevalueofthepowerindexresultingfromthepresentstudyis-1/3.83ifonlyadependenceontheupstreamsolarwindpressureisconsidered;(3)thepowerindexvariesfrom-1/3.1to-1/4.2dependingontheIMFdirectionandsolarwindspeed;and(4)thevalueofthepowerindexincreasestoorabove-1/6iftheorbitalspacecraftlimitationsarenothandledproperly.

ScienceObjectivesforSoftX-rayMissionstotheEarth'sMagnetosphere

D.G.Sibeck1,H.K.Connor1,C.P.Escoubet2,G.Branduardi-Raymont3,C.Wang4,andS.Sembay5

1NASA/GSFC,USA,2ESA/ESTEC,Netherlands,3MSSL,UnitedKingdom,4

SWL/NSSC,China,5U.Leicester,UnitedKingdomThesoftX-raysemittedwhenhighchargestatesolarwindionsexchangeelectronswithexosphericneutralsilluminatetheEarth'sdaysidemagnetosheathandcusps,outliningthepositionsofthebowshock,magnetopause,andcusps.Workinginconjunctionwithinsitusolarwindobservationsandfarultravioletimagersoftheauroraloval,widefield-of-viewsoftX-rayimagerscandeterminethenatureoftheglobalsolarwind-magnetosphereinteraction,includingreconnectionatthemagnetopause,thenatureofthesubstormcycle,andtheeffectsoftheringcurrentuponbothdaysideandnightsideprocesses.Thispresentationaddressessomeofthemoresalienttopicssuitableforanywidefield-of-viewsoftX-raymission.

NewimagingoftheSun-Earthconnection:theSMILEmission

C.P.Escoubet1,G.Branduardi-Raymont2,C.Wang3,S.Sembay4,L.Dai3,L.Li3,E.Donovan5,E.L.Spanswick5,D.Sibeck6,A.Read4,D.Rebuffat1,A.Wielders1,J.

Zheng3,J.Romstedt1,W.Raab1,D.Lumb1

1ESA/ESTEC(Netherlands),2MSSL-UCL(UK),3NSSC/CAS(China),,4LeicesterU.(UK),5CalgaryU.(Canada),6GSFC(USA)

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TheinteractionbetweenthesolarwindandtheEarth'smagnetosphere,andthegeospacedynamicsthatresult,compriseafundamentaldriverofspaceweather.Understandinghowthisvastsystemworksrequiresknowledgeofenergyandmasstransport,andcouplingbetweenregionsandbetweenplasmaandneutralpopulations.InsituinstrumentsonafleetofsolarandsolarwindobservatoriesnowprovideunprecedentedobservationsoftheexternalSun-Earthconnectiondrivers.However,wearestillunabletoquantifytheglobaleffectsofthosedrivers,includingtheconditionsthatprevailthroughoutgeospace.ThisinformationisthekeymissinglinkfordevelopingacompleteunderstandingofhowtheSungivesrisetoandcontrolsEarth'splasmaenvironmentandspaceweather.SolarwindMagnetosphereIonosphereLinkExplorer(SMILE)isanovelself-standingmissiondedicatedtoobservingthesolarwind-magnetospherecouplingviasimultaneousinsitusolarwind/magnetosheathplasmaandmagneticfieldmeasurements,X-Rayimagesofthemagnetosheathandpolarcusps,andUVimagesofglobalauroraldistributions.RemotesensingofthecuspswithX-rayimagingisnowpossiblethankstotherelativelyrecentdiscoveryofsolarwindchargeexchange(SWCX)X-rayemission,firstobservedatcomets,andsubsequentlyfoundtooccurinthevicinityoftheEarth'smagnetosphere.SMILEisacollaborativemissionbetweenESAandtheChineseAcademyofSciences(CAS)thatwasselectedinNovember2015andisdueforlaunchattheendof2021.TheSMILEscienceaswellastheresultsoftheon-goingstudyundertakenjointlybyESAandCASwillbepresented.

Theroleofturbulenceinheatingandacceleratingparticles:theTHORmission

C.P.Escoubet1,A.Vaivads2,A.Retino3,Y.Khotyaintsev2,J.Soucek4,F.Valentini5,C.Chen6,A.Fazakerley7,B.Lavraud8,9,F.Marcucci10,Y.Narita11,R.Vainio12,T.

Voirin1,A.Wielders1,N.Boudin1,J.Romstedt1

1ESA/ESTEC(Netherlands),2IRF-U(Sweden),3LPP(France),4IAP/CAS(CzechRepublic),5CalabriaU.(Italy),6ImperialCollege(UK),7MSSL(UK),8UniversityofToulouse,IRAP(France),9CNRS,IRAP(France),10INAF(Italy),11IWF(Austria),

12UniversityofTurku(Finland)

Turbulentfluctuationsinastrophysicalplasmasreachuptoscalesaslargeasstars,bubblesor'clouds'blownoutbystellarwinds,orevenentiregalaxies.However,mostoftheirreversibledissipationofenergywithinturbulentfluctuationsoccursattheverysmallscales-kineticscales,wheretheplasmanolongerbehavesasafluidandthepropertiesofindividualplasmaspecies(electrons,protons,andotherions)becomeimportant.Theenergytransferredtodifferentparticlespecies,theaccelerationofparticlestohighenergiesarestronglygovernedbykineticprocesses

25

thatdeterminehowtheturbulentelectromagneticfluctuationsdissipate.Thus,plasmaprocessesatkineticscaleswilldirectlyaffectthelarge-scalepropertiesofplasma.TurbulenceHeatingObserveR(THOR)isthefirstmissioneverflowninspacededicatedtoplasmaturbulence.Itwillexplorethekineticplasmaprocessesthatdeterminethefundamentalbehaviorofthemajorityofbaryonicmatterintheuniverse.THORwillleadtoanunderstandingofthebasicplasmaheatingandparticleenergizationprocesses,oftheireffectondifferentplasmaspeciesandoftheirrelativeimportanceindifferentturbulentregimes.THORwillprovideclosureofthesefundamentalquestionsbymakingdetailedinsitumeasurementsoftheclosestavailablediluteandturbulentmagnetizedplasmasatunprecedentedtemporalandspatialresolution.THORfocusesonparticularregions:pristinesolarwind,Earth'sbowshockandinterplanetaryshocks,andcompressedsolarwindregionsdownstreamofshocks.Theseregionsareselectedbecauseoftheirdifferingturbulentfluctuationcharacteristics,andreflectsimilarastrophysicalenvironments.THORisacandidateforselectionasthenextESAM4missionthatwilltakeplaceinJune2017andthescienceaswellastheresultsoftheon-goingstudy,currentlyundertakenatESA,willbepresented.

TheMAARBLEproject:investigatingthepropertiesofelectromagneticwavesandtheirinfluenceonthedynamicevolutionoftheVanAllenbelts

IoannisA.Daglis(1,2),SebastienBourdarie(3),RichardB.Horne(4),Yuri

Khotyaintsev(5),IanR.Mann(6),OndrejSantolik(7),DrewTurner(8),GeorgiosBalasis(2),BenjaminGrison(7)

(1)NationalandKapodistrianUniversityofAthens,DepartmentofPhysics,Athens,

Greece(2)NationalObservatoryofAthens,IAASARS,Athens,Greece

(3)ONERA,Toulouse,France(4)NERC/BAS,Cambridge,UnitedKingdom

(5)IRF,Uppsala,Sweden(6)UniversityofAlberta,DepartmentofPhysics,Edmonton,Canada

(7)IAP,Prague,CzechRepublic(8)UCLA,LosAngeles,USA

(9)nowatTheAerospaceCorporation,SpaceSciencesDepartment,LosAngeles,USA

Solarvariabilitydrives,amongotherphysicalprocesses,thegrowthoflow-frequencyelectromagneticwavesintheterrestrialmagnetosphere.Theresultingwave-particleinteractionsintheinnermagnetosphereplayacriticalroleinradiationbeltdynamics.TheMAARBLE(Monitoring,AnalyzingandAssessingRadiationBeltLossandEnergization)project,whichwasimplementedwithsupport

26

fromtheEuropeanCommunity'sSeventhFrameworkProgramme,investigatedindetailthepropertiesofthesewavesandtheparticularthewaysinwhichthesewavesmayinfluencetheenergizationandlossofradiationbeltelectrons.TheMAARBLEprojectemployedmulti-spacecraftmonitoringofthegeospaceenvironment,complementedbyground-basedmonitoring,inordertoanalyzeandassessthephysicalmechanismsleadingtoradiationbeltparticleenergisationandloss.MAARBLEcreatedadatabasebasedonmeasurementsfromtheCluster,THEMISandCHAMPmissionsandfromtheCARISMAandIMAGEgroundmagnetometernetworksandcontainingpropertiesofULFandVLFwaves.ThedatabaseisavailabletothescientificcommunitythroughtheClusterScienceArchiveasauxiliarycontent.Basedonthewavedatabase,statisticalmodelsofthewaveactivitydependentonthelevelofgeomagneticactivity,solarwindforcing,andmagnetosphericregionhavealsobeendeveloped.Multi-spacecraftparticlemeasurementshavebeenincorporatedintodataassimilationtools,leadingtoamoreaccurateestimateofthestateoftheradiationbelts.ThesynergyofwaveandparticleobservationsatthecoreofMAARBLEresearchstudiesofradiationbeltdynamicsenabledsignificantadvancesinunderstandingthenatureofthephysicalprocessesresponsible.InparticularnewunderstandingofthenatureofULFinteractions,bothcoherentanddiffusive,andbetterrepresentationsofmultipleplasmawave-particleinteractionsleadtobothnewphysicalinsightsandtherebyalsotoimprovedcoupledmodels.Resultsandconclusionsfromthesestudieswillbepresentedinthispaper.

UnderstandingtheradiationenvironmentintheEarth'sinnermagnetosphere

N.Ganushkina,andSPACESTORMandPROGRESSteams

FinnishMeteorologicalInstitute,Helsinki,Finland/UniversityofMichigan,Ann

Arbor,MI,USAEarth'sinnermagnetosphereistheregionwherespaceweathereffectsarepresent.Evenduringquietgeomagneticperiods,itisfullofdynamicprocesses.Thenumberofsatellitesonorbithasgrownsignificantlytomorethan1000.SpaceweathereventscanincreaseradiationlevelsbyfiveordersofmagnitudeintheEarth'sradiationbeltsandtriggerburstsofhighenergyparticleswhichcandisruptsatelliteoperationsandsometimescauseacompletesatelliteloss.EUFP7SPACESTORMprojectisforassessingandmitigatingoftheimpactofspaceweather.Wepresenttherecentresultsfromthisprojectondata,models,andplasmatheorystudiestodefinetheradiationenvironmentforextremespaceweathereventswithaspecificfocusontheradiationenvironmentformediumEarthorbitandgeostationaryorbit.ThedriverforthespaceweathereffectsistheSun.TheoverallgoaloftheEUH2020PROGRESSprojectistoproduceasetofforecasttoolstoaccuratelypredicttheoccurrenceandseverityofspaceweatherevents.Wedemonstratetherecent

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advancesmadeforthedevelopmentofsuchtoolswhichincludetheforecastofthethesolarwindparametersjustupstreamoftheEarth'smagnetosphere,geomagneticindices,andtheradiationenvironmentintheradiationbelts.

InteractionofULFwaveswithdifferentionspecies:pitchangleandphasespacedensityimplications

Q.-GZong,JieRen,X.Z.Zhou,R.Rankin,Y.F.Wang

PekingUniversity

ULFwavescanaccelerate/deceleratethechargedparticlesincludingtheringcurrentionsviadrift-bounceresonance,whichplayanimportantroleinthedynamicsofringcurrentduringstormtimes.Thisstudycomparesthedifferentbehaviorsofoxygenions(10.5-35.1keV)andprotons(0.3-12.3keV)whichsimultaneouslyinteractwithPc5ULFwavesobservedbyClusteronJune03,2003.TheULFwavesareidentifiedasthefundamentalmodeoscillations.Bothoxygenionsandprotonsshowperiodicenergydispersionandpitchangledispersionsignatures,whichsatisfythedrift-bounceresonanceconditionofN=2.Thedifferentbehaviorsofoxygenionsandprotonsinclude:(1)theresonantenergyofoxygenionsishigherthanthatofprotonsduetomassdifference;(2)thephasespacedensity(PSD)ofoxygenionsshowrelativevariations(3.6-6.3)thataremuchlargerthanthatofprotons(<0.4),whichindicatesamoreefficientenergyexchangebetweenoxygenionsandULFwaves;(3)thePSDspectrashowthatoxygenionsareaccelerated,whileprotonsaredecelerated,whichdependontheradialgradientoftheirPSD;(4)thepitchangledistributions(PADs)oftheoxygenionsandprotonsshownegativeslopeandbidirectionalfield-alignedfeatures,respectively,whichisrelatedtothepreexistingstateofionPADsbeforetheinteractionwiththeULFwaves.Inaddition,theresonantionswithpeakmfluxestracingbacktothemagneticequatorarealwayscollocatedwiththeaccelerating(westward)electricfield,whichindicatethattheionsaremainlyacceleratednearthemagneticequatorandtheelectricfieldintensityofULFwavespeaksthere.

OntheElegantDynamicsoftheUltra-relativisticVanAllenRadiationBelt:HowULFWaveTransportExplainsanApparentlyDiverseResponsetoSolar

WindForcing

Mann1,IanR.,L.G.Ozeke1,K.R.Murphy2,S.Claudepierre3,I.J.Rae4,D.K.Milling1,A.Kale1,andD.N.Baker5

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1.UniversityofAlberta,Edmonton,Canada.2.NASAGoddardSpaceflightCentre,Greenbelt,MD,USA.

3.TheAerospaceCorporation,LosAngeles,USA.4.MullardSpaceScienceLab.,UniversityCollegeLondon,UK.

5.LaboratoryforAtmosphericandSpacePhysics,UniversityofColorado,Boulder,USA.

TheNASAVanAllenProbeshaveopenedanewwindowonthedynamicsofultra-relativisticelectronsintheVanAllenradiationbelts.Underdifferentsolarwindforcingtheouterbeltisseentorespondinavarietyofapparentlydiverseandsometimesremarkableways.Forexample,sometimesathirdradiationbeltiscarvedout(e.g.,September2012),orthebeltscanremaindepletedfor10daysormore(September2014).Moreusuallythereisasequentialresponseofastrongandsometimesrapiddepletionfollowedbyare-energization,thelatterincreasingouterbeltelectronfluxbyordersofmagnitudeonhourtimescalesduringsomeofthestrongeststormsofthissolarcycle(e.g.,March2013,March2015).Suchdynamicsalsoappeartobealwaysboundedatlow-LbyanapparentlyimpenetrablebarrierbelowL~2.8throughwhichultra-relativisticelectronsdonotpenetrate.ManystudiesintheVanAllenProbeserahavesoughtexplanationsfortheseapparentlydiversefeatures,oftenincorporatingtheeffectsfrommultipleplasmawaves.Incontrast,weshowhowthisapparentlydiversebehaviourcaninsteadbeexplainedbyonesimpledominantprocess:ULFwaveradialtransport.OnceULFwavetransportratesareaccuratelyspecifiedbyobservations,andcoupledtothedynamicalvariationoftheouterboundaryconditionattheedgeoftheouterbelt,theobserveddiverseresponsescanallbeexplained.Inordertogetgoodagreementwithobservations,themodelingrevealstheimportanceofstillcurrentlyunexplainedfastlossinthemainphasewhichdecouplespre-andpost-stormultra-relativisticelectronfluxonhourtimescales.Similarly,varyingplasmasheetsourcepopulationsareseentobeofcriticalimportancesuchthatnear-taildynamicslikelyplayacrucialroleinVanAllenbeltdynamics.Nonetheless,simplemodelsincorporatingaccuratetransportratesderiveddirectlyfromULFwavemeasurementsareshowntoprovideasinglenatural,compelling,andattimeselegantexplanationforsuchpreviouslyunexplainedandapparentlydiverseresponsestosolarwindforcing.

MMSObservationsofEnergeticElectronMicroinjections

J.F.Fennell(1),D.L.Turner(1),C.L.Lemon(1),A.Jaynes(2),J.B.Blake(1),J.H.Clemmons(1),D.N.Baker(2),B.H.Mauk(3),I.J.Cohen(3),H.E.Spence(4)

(1)TheAerospaceCorp.LosAngeles,CA90009,USA(2)LASPUniversityofColorado,Boulder,CO,USA

(3)JohnsHopkinsAppliedPhysicsLaboratory,Laurel,MD,USA(4)UniversityofNewHampshireSpaceScienceCenter,Durham,NH,USA

29

TheearlyMMSenergeticelectrondatatakeninthedusktopremidnightregionsabove~9REshowedmanyclustersofelectroninjectionswecallmicroinjectionsbecauseoftheirshortdurationsignatures.Thesemicroinjectionsof50-400keVelectronshaveenergydispersionsignaturesindicatingthattheygradientandcurvaturedriftedfromearlierlocaltimes.Aparticularclusterofabout40electronmicroinjectionsoccurredina4.5-hourintervalstartingat21:15UTon6August2015.Weshowdetailedresultsfrommicroinjectionstakenwithburstmodedatastartingnear21:16UT.Thesehightemporalresolutiondatashowedthattheelectronsinthemicroinjectionsweretrappedandhadbidirectionalfield-alignedangulardistributions.Driftcalculationsconstrainedbytheobservedelectrondispersiontimesindicatetheelectronshaddriftedfromnearthemagnetopauseapproximatelytwohoursearlierinlocaltime.ManymultipleclustersofmicroinjectionswereobservedasMMSapogeetraversedthepremidnighttoduskregion.TheywerenotobservedastheMMSapogeepassedfromduskthroughthedaysideregions.Later,astheMMSapogeeonceagainmovedthroughthemidnighttopremidnightregion,duringmissionphase1X,injectionswereonceagainobserved.Weprovidestatisticsontheoccurrenceoftheinjectionsanddiscusspossibleimplications.Theseinjectionclustersareanewphenomenoninthisregionofthemagnetosphere.

Clusterobservationsofmagnetosonicwavesintheinnermagnetosphere.

S.N.Walker(1),K.H.Yearby(1),S.A.Boardsen(2,3),D.G.Sibeck(3),andM.A.Balikhin(1)

1DepartmentofControlEngineering,UniversityofSheffield2GoddardPlanetaryandHeliophysicsInstitute,UniversityofMaryland,Baltimore,

Maryland,USA3NASA/GSFCGreenbelt,Maryland,USA

Observationsofmagnetosonicwavestypicallyexhibitemissionsatharmonicsoftheprotongyrofrequencythatpersistfromseveralminutestoanhourorlonger.Recentobservationshaveshowntheexistenceofnon-timecontinuousexamplesofmagnetosonicwaves.Inthispaperweinvestigatethepropertiesofthesenon-timecontinuous,reportingonastatisticalstudyoftherateoffrequencychangefortherisingtoneemissionfeaturesandthecontrolmoreintermittentemissionsappeartobecontrolledbytheplasmadensity.Thefrequencystructureofpersistentmagnetosonicwavesshowsevidenceforemissionsbetweenthegyroharmonicfrequencies.Thesourceofthesewavesisinvestigatedbeexaminingtheir

30

propagationdirectiontodetermineiftheirgenerationislocalornon-local.

CanEMICtriggeredemissionsbegeneratedoffthemagneticequatorialplane?

BenjaminGrison(1),HugoBreuillard(2),OndrejSantolik(1),NicoleCornilleau-Wehrlin(3)andMiroslavHanzelka(1)

(1)InstituteofAtmosphericPhysicsACSR,Praha4,CzechRepublic,

(2)LaboratoiredePhysiquedesPlasmas,LPP/CNRS/UniversitéPierreetMarieCurie,Paris,France

(3)LPPP/CNRS-EcolePolytechnique,Palaiseau,FranceElectroMagneticIonCyclotron(EMIC)triggeredemissions(TEs)resultfrominteractionbetweenenergeticprotons(>1keV)andEMICwavesintheinnermagnetosphereandinthedaysideregions.Thefrequencywithtimedispersionandthehighcoherencelevelofthewavesarecharacteristicsoftheseemissions.Theyplayaroleinprotonprecipitationsandtheirinfluencecanbestrongerinlargermagnetospheres(atSaturnorJupiter,forexamples).EMICtriggeredemissionshavebeenrecentlyobservedinsitubyClusterandTHEMISspacecraft.Uptoourknowledgealleventsareobservedclosetomagneticequatorialplane,atmagneticlatitudes(MLAT)lowerthan15deg.Thesourceregionhasbeenfoundinthevicinityoftheequatorialplaneforalltheseevents.InthepresentstudywefocusonthreedistinctClusterevents.IneachofthiseventoneormoreEMICtriggeredemissionsareobservedbyoneormoreClusterspacecraftoffthemagneticequatorialplane(>20degMLAT).OneoftheseeventsisofparticularinterestbecausemanyTEsoccuratperiodictimeinterval.Wefirstpresentadetailedpolarizationanalysisofthesewaves.Themagneticwaveform(STAFFinstrumentdata)istransformedintotheFourierspaceforastudybasedonsingularvaluedecomposition(SVD)analysis.Unfortunately,thePoyntingfluxorientationcouldnotbeestablished.Thenwecompareourresultstotheobservationofpreviouscases.Inordertoidentifythesourceregionwestudytwopossibilities:asourceregionathigherlatitudesthantheobservations(andparticlesorbitingin'Shabansky'orbits)andasourceregionclosetothemagneticequatorialplane,asreportedinpreviousstudies.Theresultsarecompletedwithapreliminaryray-tracinganalysis.

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Finestructureembeddedinwhistlermodechoruswavepackets:observationsofClusterandVanAllenProbesintheinnermagnetosphere

OndrejSantolik1,2;IvanaKolmasova1,2;JolenePickett3,WilliamS.Kurth3,GeorgeB.Hospodarsky3,DonaldA.Gurnett3,CraigA.Kletzing3,andScottR.

Bounds3

1InstituteofAtmosphericPhysicsCAS,Prague,Czech2FacultyofMathematicsandPhysics,CharlesUniversity,Prague,Czechia

3UniversityofIowa,IowaCity,Iowa,USA

Electromagneticwhistler-modechoruswavesareamongthemostintensenaturallyoccurringemissionsintheinnermagnetosphere.TheiramplitudesathundredsofHztoseveralkHzfrequenciescanreach1%ofthebackgroundmagneticfield.ThesewavescanplayasignificantroleintheprocessoflocalaccelerationofrelativisticelectronsandtheycanthereforestronglyinfluencethedynamicsoftheouterVanAllenradiationbelt.Investigationofthenonlineargenerationprocessofchorusisasubjectofasignificanteffortintheoreticalstudiesandnumericalsimulations,aimingatmicrophysicsofwave-particleinteractions.Assumptionsofthesestudiesneedtobeconstrainedbyinsituobservations.WeusemeasurementsoftheWideBandData(WBD)instrumentonboardClusterspacecraftaswellasmeasurementsoftheWavesinstrumentoftheElectricandMagneticFieldInstrumentSuiteandIntegratedScience(EMFISIS)onboardtheVanAllenProbestoanalyzeintensechorusAlargedatabaseofmulticomponentandmultipointwaveformdatahasbeencollectedbytheseinstruments.Weuseselectedintervalsofchorusandwedeterminetheinstantaneousamplitudes,phases,frequencies,andwavevectordirectionsofchoruswaveforms.Finestructureembeddedinthechoruselementsmainlyreflectsthesimultaneouspresenceofwavesatdifferentfrequencies(sidebands)althoughseparatewavepacketsarealsoobserved.Theobservedfrequencydifferences(timescalesofsubpackets)donotseemtoscalewithamplitudeasdoesthetheoreticaltrappingfrequency.Ourresultsfurthershowthatpeakvaluesoftheinstantaneousamplitudedecreasewiththedistancefromthemagneticequatorandwiththetimeintervalbetweenpeaks.

Theinnermagnetosphereioncomposition

C.G.Mouikis,L.M.Listler

UniversityofNewHampshire

32

Themagnetosphericplasmaisamulti-speciesplasmaanditisknownthatduringsolarandgeomagneticallyactivetimes,O+ionsofionosphericorigincancontributesignificantlyto,ifnotdominate,thedensityandpressurebothinthemagnetotailandintheinnermagnetosphere.AddingO+,fromthecuspsandthroughthelobes,tothenormallyH+dominatedmagnetotailplasmasheet,significantlychangestheplasmasheetmassdensity.Thisisotropizedhotpopulation,throughinwardconvection,becomesthemaincontributorofthestormtimeringcurrentpressure.Theauroraloutflow,whichenterstheplasmasheetclosertotheearth,wheretheradiusofcurvatureofthefieldlineislarger,doesnotisotropizeorbecomesignificantlyenergized,butremainsapredominantlyfieldalignedlowenergypopulationintheinnermagnetosphere.ThusitappearsthattheO+thatenterstheplasmasheetfurtherdownthetailhasagreaterimpactonthestorm-timeringcurrentthanionsthatenterclosertotheearth.Thesourcepopulationofthestormtimeringcurrentisthenightsideplasmasheet.However,theringcurrentrespondsdifferentlytothedifferentsolarandinterplanetarystormdriverssuchascoronalmassinjections,(CME's),co-rotatinginteractionregions(CIR's),high-speedstreamersandotherstructures.Theresultingchangesintheringcurrentparticlepressurechangetheglobalmagneticfield,whichaffectsthetransportoftheradiationbelts.Inordertodeterminethefieldchangesduringastorm,itisnecessarytounderstandthetransport,sourcesandlossesoftheparticlesthatcontributetotheringcurrent.

ObliqueWhistler-ModeWavesintheEarth'sInnerMagnetosphere

OleksiyAgapitov,AntonArtemyev,DidierMourenas,VladimirKrasnoselskikh,ForrestMozer

SSLUCBerkeley,USA;UCLAUCLosAngeles,USA;LPC2ECNRS-Universityof

Olreans,France;Therecentspacecraftobservationsofobliquewhistler-modewavesintheEarthinnermagnetosphere,aswellasthevariousconsequencesofthepresenceofsuchwavesforelectronscatteringandacceleration,arepresented.Thestatisticsofoccurrencesandintensityofobliquechoruswavesintheregionoftheouterradiationbelt,comprisedbetweentheplasmapauseandgeostationaryorbitisperformed.Wefurtherexaminehowsuchobliquewavepopulationscanbeincludedintobothquasi-lineardiffusionmodelsandfullynonlinearmodelsofwave-particleinteraction.Onthisbasis,wedemonstratethatvaryingamountsofobliquewavescansignificantlychangetheratesofparticlescattering,acceleration,andprecipitationintotheatmosphereduringquiettimesaswellasinthecourseofastorm.Wedemonstratethatobliquewhistler-modechoruswavescanbeconsideredasanimportantingredientoftheradiationbeltsystemandcanplayakeyroleinmanyaspectsofwave-particleresonantinteractions.

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CofelectricradialdiffusioncoefficientofradiationbeltelectronswithinsituelectricfieldmeasurementsbyTHEMIS

WenlongLiu,WeichaoTu,XinlinLi

BeihangUniversity,WestVirginiaUniversity,UniversityofColorado

Basedonsevenyears'observationsfromTHEMIS,weinvestigatethestatisticaldistributionofelectricfieldPc5ULFwavepowerunderdifferentgeomagneticactivitiesandcalculatetheradialdiffusioncoefficientduetoelectricfield,DLLE,forouterradiationbeltelectrons.AsimpleempiricalexpressionofDLLE[THEMIS]isalsoderived.SubsequentlywecompareDLLE[THEMIS]topreviousDLLmodels,andfindsimilarKpdependencewiththeDLLE[CRRES]model,whichisalsobasedonin-situelectricfieldmeasurements.TheabsolutevalueofDLLE[THEMIS]isconstantlyhigherthanDLLE[CRRES],probablyduetothelimitedorbitalcoverageofCRRES.ThedifferencesbetweenDLLE[THEMIS]andthecommonly-usedDLLB[B-A]andDLLE[Ozeke]modelsaresignificant,especiallyinKpdependenceandenergydependence.Possiblereasonsforthesedifferencesandtheirimplicationsarediscussed.Thediffusioncoefficientprovidedinthispaper,whichalsohasenergydependence,willbeanimportantcontributortoquantifytheradialdiffusionprocessofradiationbeltelectrons.

Plasmasphericplumeanalysisduringthe2013Clustercloseseparationcampaign,augmentedwithVanAllenProbesdataandaplasmapausetest

particlesimulation

F.Darrouzet(1),J.DeKeyser(1),P.M.E.Decreau(2),J.Goldstein(3),W.Kurth(4),S.DePascuale(4),O.Santolik(5,6)

(1)RoyalBelgianInstituteforSpaceAeronomy(IASB-BIRA),3AvenueCirculaire,

1180Brussels,Belgium(2)LaboratoiredePhysiqueetChimiedel'Environnementetdel'Espace(LPC2E),

Orleans,France(3)SouthwestResearchInstitute(SwRI),SanAntonio,TX,USA

(4)UniversityofIowa(Uiowa),IowaCity,IA,USA(5)InstituteofAtmosphericPhysics-CzechAcademyofSciences(UFA-CAS),Praha,

CzechRepublic(6)FacultyofMathematicsandPhysic-CharlesUniversityinPrague(MFFUK),

Praha,CzechRepublicDuringthelastClustercloseseparationcampaign(July-October2013),twoofthefourClustersatelliteswereonlytensofkilometersapart,whilethetwootherswerelocatedatafewhundredsofkilometers.Thisconfigurationoffersanexceptionalopportunitytoanalyzetheplasmaspherewithveryhighspaceandtimeresolution

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aroundthetimeofperigeeatabout4RE.Inparticular,plasmasphericplumeswerecrossedbythesatellitesonseveraloccasions.Thiscontributionpresentssuchaneventon13July2013withelectrondensitydataobtainedfromtheWHISPERinstrumentonboardCluster.Aplasmapausetestparticlesimulationisusedtoprovideaglobalviewoftheplasmasphereandplasmapause.Also,theelectrondensityinsidetheplumeisinferredfromEMFISIS/WavesobservationstakenonboardthetwoVanAllenProbes,whichcrossedthesameplumeandprovideanotherview.Theinitialformationandglobalevolutionoftheplumearestudiedusingthegeneralcontextanddatafromthesatellitesattheirrespectivelocations.Densityirregularitiesareobservedinsidetheplume.Someareverystableatonlyafewminutesscale,whileotherspersistalsoatlongerscales.Theirspatialgradientisstudiedaswellastheirmotionwiththehelpofmulti-spacecraftanalysis.Recentresultsaboutwavesobservedduringtheplumecrossingswillbealsopresented.

Lightningwhistlerstriggeringplasmaspherichiss:multi-spacecraftobservationsandray-tracinganalysis

I.Kolmasova1,2;O.Santolik1,2;M.Hanzelka2,1;J.S.Pickett3;W.S.Kurth3,and

C.A.Kletzing3

1InstituteofAtmosphericPhysics,CzechAcademyofSciences,Prague,CzechRepublic

2FacultyofMathematicsandPhysics,CharlesUniversity,Prague,CzechRepublic3DepartmentofPhysicsandAstronomy,UniversityofIowa,IowaCity,Iowa,USA

SeriesoflightningwhistlerswererecordedbytheWide-BandData(WBD)instrumentsonboardthreeClusterspacecraft(C1,C3,andC4)duringtheClusterInnerMagnetospherecloseseparationcampaignonthe4thofJuly2013.Ourdatasetiscomposedofhigh-resolutionwaveformsoflightningwhistlerswhichoccurredfrom12:00to12:10UTwhenthespacecraftweremovingfromtheSouthtotheNorthclosetotheequatoratRE~3.5.ThesatellitedatawerecompletedbytheWWLLNandEUCLIDlightningdetectiondata.Thetime-frequencyspectrogramsoftheobservedseriesoflightningwhistlersexhibittwodifferentspecificpatterns.Inthefirstgroupofcasesweobserveintenseburstsofplasmaspherichissatfrequenciesbelow2kHzwhichareclearlyrelatedtolightningwhistlers.Nosuchtriggeredhissemissionsareobservedinthesecondgroupofcases.Usingmulti-spacecraftanalysiswithestimationofthecausativelightningstrokelocationsweinvestigatedifferencesinpropagationofthesetwogroupsoflightningwhistlers.Resultsofouranalysisleadustoahypothesisthatlightningwhistlerspenetratingtheionosphereatlowerlatitudesandpropagatingunductedmaybeoneofthesourcesofplasmaspherichissbelow2kHz.Weverifythishypothesisusinga

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raytracinganalysisbasedonthedensityprofilederivedfrommeasurementsofElectricandMagneticFieldInstrumentSuiteandIntegratedScienceinstrument(EMFISIS)onboardVanAllenProbespacecraft.

Erosionandrefillingoftheplasmaspherestudiedbyneuralnetworkbasedthree-dimensionalplasmasphericmodel

XiangningChu(1)JacobBortnik(1)

WenLi(1)VassilisAngelopoulos(2)RichardMThorne(1)

RichardEugeneDenton(3)JohnDouglasMenietti(4)

YongliWang(5)

(1)UniversityofCaliforniaLosAngeles,DepartmentofAtmosphericandOceanicSciences,LosAngeles,CA,UnitedStates,

(2)UniversityofCaliforniaLosAngeles,Earth,Planetary,andSpaceSciences,LosAngeles,CA,UnitedStates,

(3)DartmouthCollege,Hanover,NH,UnitedStates,(4)UniversityofIowa,PhysicsandAstronomy,IowaCity,IA,UnitedStates,(5)UniversityofMarylandBaltimoreCounty,GoddardPlanetaryHeliophysics

Institute,Baltimore,MD,UnitedStates

Wedevelopedatime-dependentglobalplasmadensitymodeloftheinnermagnetospherewhichusesafeedforwardneuralnetworkschemawithtwohiddenlayers.Asthemodeloutput,weusedtheelectrondensityinferredfromspacecraftpotentialfromthreeTHEMISprobes.Asthemodelinputs,wetookthespacecraftlocation(L,magneticlocaltimeandlatitude),andtimeseriesoftheSYM-H,ALandF10.7indices.Theequatorialelectrondensityisshowntobeaccuratelyreconstructedwithacorrelationofr~0.953betweenmodeloutputandobservations.Themodelsucceededinreconstructingthedistributionanddynamicsofthedensity,includingthequiettimeplasmasphere,erosionandrecoveryoftheplasmasphere,aswellastheplumeformationduringastormonFebruary04,2011.Themodelalsoreproducedthecontractionandrecoveryoftheplasmapauseforthesameevent.Theneuralnetworkbasedplasmasphericmodelisthenexpandedtothreedimensionsbyincludingmoreobservationsfrombothequatorialsatellitesandpolarorbitingsatellites(RBSP,CRRES,ISEE,CLUSTER,POLAR,IMAGE).Wemaintainthesamearchitectureoftheneuralnetworkmodel(twohiddenlayers)

36

andthemodelinputs(locationandtimeseriesofSYM-H,ALandF10.7indices).Thethree-dimensionalplasmasphericmodelcanreproducealmost90%ofthevariationintheplasmadensitywithacorrelationofr~0.943.Usingthethree-dimensionalplasmasphericmodel,wereconstructatime-dependentthree-dimensionalplasmasphere.Thelatitudinalprofileoftheplasmadensityiscomparedwiththoseprofilesfrompreviousstudy.Inaddition,weshowtheevolution(erosionandrefillingandplumeformation)oftheplasmasphereduringgeomagneticstormsinathree-dimensionalperspective.

Thegeospaceexplorationproject:ERG

Y.Miyoshi(1),I.Shinohara(2),T.Takashima(2),K.Asamura(2),H.Matsumoto(2),N.Higashio(2),T.Mitani(2),S.Kasahara(3),S.Yokota(2),S-Y.Wang(4),Y.Kazama(4),

Y.Kasahara(5),Y.Kasaba(6),S.Yagitani(5),A.Matsuoka(2),H.Kojima(7),Y.Katoh(6),K.Shiokawa(1),K.Seki(3),M.Fujimoto(2),T.Ono(6),andERGproject

team

(1)NagoyaUniversity,Japan,(2)JAXA,Japan,(3)UniversityofTokyo,Japan,(4)ASIAA,Taiwan,(5)KanazawaUniversity,(6)TohokuUniversity,(7)Kyoto

UniversityTheERG(ExplorationofenergizationandRadiationinGeospace)isJapanesegeospaceexplorationproject.Theprojectfocusesonthegeospacedynamicsinthecontextofthecross-energycouplingviawave-particleinteractions.Theprojectconsistsofthesatelliteobservationteam,theground-basednetworkobservationteam,andintegrated-dataanalysis/simulationteam.ThedevelopmentofthesatelliteisthefinalstageandwillbelaunchedinFY2016.Comprehensiveinstrumentsforplasma/particles,andfield/wavesareinstalledintheERGsatellitetounderstandthecross-energycouplingsystem.IntheERGproject,severalground-networkteamsjoin;magnetometernetworks,radarnetworks,opticalimagernetworks,etc.Moreover,themodeling/simulationsplayanimportantroleforthequantitativeunderstanding.Forthedataanalysisenvironment,theERGprojecthasdevelopedseveralplug-insforSPEDASincollaborationswiththeTHEMISmission.TheERGprojectdatawillbedownloadedandanalyzedusingtheSPEDAS.Inthispresentation,wewilltalkaboutanoverviewoftheERGprojectandpossiblecollaborationswithTHEMISandClustermissionsandothergeospaceprojects.

Electricfieldsassociatedwith100skeVelectronenhancementsintheslotregion

SamCaliff,XinlinLi,HongZhao,AllisonJaynesandDavidMalaspina

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LaboratoryforAtmosphericandSpacePhysics

Thedouble-probeinstrumentsonboardCRRES,THEMISandtheVanAllenProbeshaveshownthatstrongquasi-staticelectricfieldscanreachlowLshells(L<3)intheinnermagnetosphereduringgeomagneticallyactivetimes.Theseelectricfieldscanberelatedtoanumberofmechanismsincludingpenetrationoftheconvectionelectricfield,subauroralpolarizationstreams,substorminjections,interplanetaryshocksandneutralwinds.Quasi-staticelectricfieldsaffectplasmathroughExBdriftandareusuallyassociatedwiththedynamicsofthelow-energyplasmasphere.Higher-energyparticlesintheringcurrentandradiationbeltsarealsoinfluencedbylarge-scaleelectricfields,whereinwardradialtransportthroughazimuthalelectricfieldscanincreasetheenergyoftheparticles.RecentobservationsbytheVanAllenProbesshowfrequentenhancementsof100skeVelectronsintotheslotregionandinnerbelt(L<3),withlowerenergiesreachinglowerLshellsmorefrequently.WeexploreinsituelectricfieldmeasurementsbyTHEMISandtheVanAllenProbessurroundingtheseenhancementstoinvestigatetheimpactofquasi-staticelectricfieldson100skeVelectrondynamicsdeepwithintheinnermagnetosphere.

ParticleAccelerationinSolarFlaresandTerrestrialSubstorms

M.Oka

UCBerkeleyParticlesareacceleratedtoveryhigh,non-thermalenergiesduringexplosiveenergy-releasephenomenasuchassolarflaresandterrestrialsubstorms.Whileithasbeenestablishedthatmagneticreconnectionplaysakeyroleinthesephenomena,theprecisemechanismofparticleaccelerationviareconnectionisstillunclear.Hereweshow,basedonacompilationofpreviouslyreportedobservations,thatthepower-lawindexdmayhavealower-limitatd~4inbothsolarflaresandterrestrialsubstorms(i.e.,d>~4),wheredisdefinedinthefluxdensity(differentialflux)distribution.Thisisinstarkcontrasttothecaseofparticleaccelerationatshocks(suchasinterplanetaryshocksandtheterrestrialbowshock)whosepower-lawindexoftenexceedsthelimit(i.e.,d<~4).Theseresultssuggestthefollowings:(1)theremaybeacommonbutnot-yet-identifiedphysicsintheseentirelydifferentenvironment,i.e.thecoronaandthemagnetotail,and(2)explosiveenergy-releasephenomenasuchassolarflaresandterrestrialsubstormsarenotasefficientasshocksintermsofconvertingupstreamenergiestonon-thermalparticleenergies,atleastintheheliospheric,non-relativisticenvironmentofplasmas.

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AnAnalysisofMagneticReconnectionEventsandtheirAssociatedAuroralEnhancements

N.A.Case(1),A.Grocott(1),S.E.Milan(2),T.Nagai(3),andJ.P.Reistad(4)

(1)LancasterUniversity,(2)LeicesterUniversity,(3)TokyoInstituteofTechnology,

and(4)UniversityofBergenWepresentananalysisofsimultaneousreconnectioneventsintheearth'smagnetotailandenhancementsintheaurora.WeexploitmagnetosphericdatafromtheGeotail,Cluster,andDoubleStarmissions,alongwithauroralimagesofbothhemispheresfromtheImageandPolarmissions,toexploretherelationshipbetweenareconnectionsignatureanditsauroralcounterpart.Fromastudyof46suitablereconnectionevents,wefindthat36demonstrateaclearcoincidenceofreconnectionandauroralenhancement.These36enhancementsandreconnectionsitesaregenerallylocatedwithin+/-1hourMLTofeachotherandthereisagoodcorrelationbetweentheMLTsofboth(r=0.7).Theenhancementsarelocalizedandoftenshortlived(<10mins)andoccurequallybeforeandafterthesubstormonset.NosignificantdependencebetweenthereconnectionandauroralenhancementlocationisfoundwithlocalByorVy,orIMFBy.SomesmalldependenceisevidentforsolarwindVy.

Magnetotailfastflowsnearlunarorbit

KiehasStefan(1),RunovAndrei(2),AngelopoulosVassilis(2),HeliHietala

(1)IWFGraz(2)UCLA

Weusefiveyears(2011-2015)ofARTEMISdatatostatisticallyinvestigateearthwardandtailwardflowsataround60REdowntail.Wefindthatasignificantportion(~50%)offastflowsisdirectedearthward.Thiscontributionreduceswithincreasingflowspeed.Asexpected,earthward(tailward)flowsarepredominantlyaccompaniedwithpositive(negative)Bz.Adawn-duskasymmetryintheflowoccurrenceisseenforbothearthwardandtailwardflowswithabout50%-60%(60%-70%)oftheearthward(tailward)flowsoccurringinthedusksector.Thisasymmetryismoredominantfortailwardthanforearthwardflowsandincreasesslightlywithhigherflowspeeds.Consideringonlytheflowcomponentperpendiculartothemagneticfield,theportionofearthwardflowsreducestoabout30%-40%,dependingontheflowspeed.Thedawn-duskasymmetryisalsoseeninthisperpendicularflows.

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MagnetotailCurrentSheetStructurefromClusterandTHEMISObservations

A.Artemyev,A.Runov,V.Angelopoulos

UCLAObservationsbytwomulti-probemissions,ClusterandTHEMIS,provideuniqueopportunitytoinvestigatebothtransverse(acrossthetail)andlongitudinal(alongthetail)currentsheetstructure.Studiesoffour-pointmagneticfieldmeasurementsbyClusterrevealedmanydetailsofinnercurrentsheetstructure.Simultaneousobservationsbythetail-elongatedTHEMISprobesdemonstratedhowcurrentsheetconfigurationvariesalongthetail.Inthispresentation,wereviewmaincurrentsheetpropertiesderivedfromClusterandTHEMISstatistics.

StudyingmagneticreconnectionusingtheFOTEmethod:ClusterandMMSresults

HuishanFu

SchoolofSpaceandEnvironment,BeihangUniversity,Beijing,China

FOTEisamethoddevelopedtofindmagneticnullsandreconstructfieldtopologyoflinearmagneticstructures;itisparticularlyusefultothefour-spacecraftmissionwithsmallseparation(e.g.,Clusterin2003andtherecentMMSmission).Inthistalk,wewillshowhowweapplythismethodtotheClusterandMMSdataandwhatresultswecanobtainfromthismethod.Specifically,westudythemagneticislandsinmagnetotail,thefluxtransferevents(FTEs)atmagnetopause,andtheX-linesandfluxropesinsideiondiffusionregionatmagnetopause.Wereconstructthetopologiesofallthesestructures(magneticislands,FTEs,X-linesandfluxropes).Also,werevealtheparticledynamicsaroundthesestructures.Thenewfindingsweobtaininclude:(1)suddenenhancementofoxygeninsidethemagneticislandsassociatedwithdipolarizationfronts;(2)significantincreaseofplasmadensityandO+fluxesinsidetheFTEstructures;(3)X-linesinsidetheelectrondiffusionregion;(4)numerouskinetic-scalefluxropesinsidetheiondiffusionregion;and(5)thestrongquadrupolarHallmagneticfieldintheguide-fieldasymmetricreconnectionevent.

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ElectricFieldsattheDipolarizationFronts:ClusterandMMSobservations

AndrisVaivads,AndreyDivin,DanielGraham,MatsAndre,ClusterTeam,MMSTeam

SwedishInstituteofSpacePhysics,UppsalaHighspeedplasmaflows,commonlyreferredtoasjets,areubiquitousinplasmaenvironments.Jetsalwaysaccompanymagneticreconnection,whichisoneofthekeyenergyconversionprocessesinmagnetizedplasmas.Jetfrontsobservedinthemagnetotail,alsocalleddipolarizationfronts,arenarrowregionswithatypicaltransversesizeofseveralioninertiallengths,withlargechangesinmagneticfield,densityandtemperature,andassociatedstrongelectromagneticandelectrostaticemissionsinabroadfrequencyrange.WepresentobservationsofelectricfieldsatdipolarizationfrontsbyClusterandMMSanddiscusstheirroleinplasmaheatingandparticleacceleration.

ElectronInjections:AStudyofElectronAccelerationbyMultipleDipolarizingFluxBundlesUsinganAnalyticalModel

C.Gabrielse,C.Harris,V.Angelopoulos,A.Artemyev,A.Runov

UCLA

Westudyenergeticelectroninjectionsusingananalyticalmodelthatself-consistentlydescribeselectricandmagneticfieldperturbationsoftransient,localizeddipolarizingfluxbundles(DFBs).PreviousstudiesusingTHEMIS,VanAllenProbes,andtheMagnetosphericMultiscaleMissionhaveshownthatinjectionscanoccuronshort(minutes)orlong(10sofminutes)timescales.ThesestudiessuggestthattheshorttimescaleinjectionscorrespondtoasingleDFB,whereaslongtimescaleinjectionsarelikelycausedbyanaggregateofmultipleDFBs,eachincrementallyheatingtheparticlepopulation.Wethereforemodeltheeffectsof(1)asingleDFBand(2)multipleDFBsontheelectronpopulationusingmulti-spacecraftobservationsofthefieldsandparticlefluxestoconstrainthemodelparameters.Theanalyticalmodelisthefirstofitskindtomodelmultipledipolarizationfrontsinordertobetterunderstandthetransportandaccelerationprocessthroughouttheplasmasheet.Itcanreproducemostinjectionsignaturesatmultiplelocationssimultaneously,reaffirmingearlierfindingsthatearthward-travelingDFBscanbothtransportandaccelerateelectronstosuprathermalenergies,andcanthusbeconsideredtheinjections'primarydriver.

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IonHeatingandAnisotropyinMagnetotailReconnectionJets

H.Hietala(1,2),J.P.Eastwood(2),J.F.Drake(3),T.D.Phan(4),A.V.Artemyev(1),R.Mistry(2),V.Angelopoulos(1)

(1)EPSS,UCLA;(2)ImperialCollege,London;(3)Univ.ofMaryland;(4)SSL,UCBerkeley

Magneticreconnectionredistributesenergybyreleasingmagneticenergyintoparticleenergies---high-speedbulkflows,heating,andparticleacceleration.Withnear-Earthinsituobservations,wehaveaccesstodifferentparameterregimes:themagnetotail,themagnetopause,andthesolarwind.Theenergeticsofmagnetotailreconnectionjetsareparticularlyinterestingastheavailablemagneticenergyperparticle(B_in^2/mu0*n_in=m_iVA,in^2)istypicallyordersofmagnitudehigherandtheinflow(lobe)plasmabetamuchlowerthaninthesolarwindandatthemagnetopause.Furthermore,thisseparationofcharacteristicspeeds(theAlfvenspeedsarehighandthethermalspeedsarelow)allowsustobetterinvestigatethedynamicsofthetwomixingpopulationsinthereconnectionexhaust.Asignificantportionoftheenergyreleasedbymagnetotailreconnectionappearstogointoionheating,andtheheatingisanisotropicwiththeplasmatemperatureparalleltothemagneticfieldgenerallyincreasingmorethantheperpendiculartemperature.Simulationsandtheoryindicatethatthistemperatureanisotropycanbalancepartofthemagnetictensionforcethatacceleratesthejet,andmayevenexceeditleadingtofirehoseinstability.HerewepresentARTEMISdual-spacecraftobservationsofanti-parallelmagneticreconnectioninthelunardistancemagnetotail.Weconsiderthespatialvariationsintheionanisotropyacrosstheoutflowfardownstream(>100ioninertiallengths)oftheX-lineforbothdensitysymmetricandasymmetricboundaryconditions.Inthecaseofsymmetricinflowconditions,plasmaiswellabovethefirehosethresholdinportionsoftheexhaust,suggestingthatthedrivefortheinstabilityisstrongandtheinstabilityistooweaktorelaxtheanisotropy.Theperpendiculartemperaturedominatesatthemid-plane,indicatingthatparticlesundergoSpeiser-likemotion.Inthecaseofasymmetricboundaryconditions(aneventwherethenorthlobehadhigh-densitymantleandboundarylayerplasmawhilethesouthlobehadamuchlowerdensity)theplasmaismostlymarginallyfirehosestable.TheHallmagneticfieldpolaritycorrespondingtothehigh-densitysideisenhanced,consistentwiththeoreticalexpectationsandstabilizingtheplasma.Wealsoanalyzethecharacteristicsoftheparticledistributionsleadingtotheseanisotropiesatdifferentdistancesfromthemid-plane.

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Electronfield-alignedanisotropyanddawn-duskmagneticfield:nineyearsofClusterobservationsintheEarthmagnetotail.

E.Yushkov(1,2),A.Petrukovich(1),A.Artemyev(1,3),R.Nakamura(4)

(1)SpaceResearchInstitute,RAS,Moscow,Russia

(2)LomonosovUniversity,Moscow,Russia(3)DepartmentofEarth,Planetary,andSpaceSciencesandInstituteofGeophysics

andPlanetaryPhysics,UniversityofCalifornia,LosAngeles,California,USA(4)SpaceResearchInstitute(IWF),AAS,Graz,Austria

ProcessingnineyearsofClusterobservationsintheEarthmagnetotail,weinvestigateelectrontemperatureanysotropyandit’sdependenceonByandBzmagneticfieldcomponents(inGSMcoordinates).WecharacteriseanysotropicelectronpopulationbytemparatureratioTpar/TperandphasespacedensityratioFpar/Fperforparallel(par)andtransverse(per)directionstobackgroundmangneticfield.WeshowthatelectronanysotropicpopulationidentefiedbylargeFpar/FperratiocanexistinplasmasheetwithsmallTpar/Tper.ThermalanysotropyTpar/TperincreasessignificantlywithBzandBy:BygrowthresultsinformationofstrongTpar/TperpeaknearthemagnetotailneutralplaneBx=0,whereasBzgrowthresultsinTpar/TperincreaseforwideBxrange.DependenciesofTpar/TperonByandBzhavedawn-duskasymmetry:Tpar/TpergrowthcorrespondstoBzincreaseatduskflankandByincreaseatdawnflank.UsingdifferencesofelectronanysotropydependenciesonByandBzmagneticfieldcomponents,wediscusspossiblemechanismsresponsibleforitsformation.

CLUSTERviewonPSBLionbeamsintheEarth'smagnetotail

GrigorenkoE.E.,L.M.Zelenyi,M.S.Dolgonosov,E.A.Kronberg,P.W.Daly

SpaceResearchInstituteofRAS,MaxPlanckInstituteforSolarSystemResearch,Göttingen,Germany,LudwigMaximilianUniversityofMunich,Munich,GermanyPlasmaSheetBoundaryLayer(PSBL)isaverydynamicregionplayinganimportantroleinthemagnetosphere-ionospherecoupling.Field-alignedhigh-velocityionbeamstransportingtheenergyfromthedistanttailtotheinnermagnetosphereareveryfrequentlyobservedinthePSBL.IndependenceontheglobalmagnetotaildynamicsthePSBLionbeamshavedifferentspatialandtemporalscales.MultipointCLUSTERobservationsallowed,forthefirsttime,apreciseestimationoftheionbeamcharacteristics.Itwasshownthatduringdifferentperiodsofthemagnetotailactivitytheionbeamsaregeneratedbydifferentregimesofthenonadiabaticacceleration.DuringquietperiodsthePSBLmayconsistfrommultiplelong-lasting(upto~20min)ionbeams,whicharelocalizedbothinvelocityandphysicalspace.Onthecontrary,thereconnection-associatedsourcesofionbeamaccelerationaretransientandusuallygeneratemoreenergeticbeamshavingashort(~1-3min)

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durationandamuchbroaderrangeofparallelvelocities.InthiscontributionthepeculiaritiesofdifferentmechanismsofionbeamaccelerationandtheirPSBLmanifestationsarediscussedandcompared.ThisworkwassupportedbytheVolskwagenFoundation(grantAz90312).

Doesthecross-scaleenergytransportassociatedwithasymmetricgrowthofKelvin-HelmholtzInstabilityexplaintheoriginofplasmasheettemperature

asymmetryofcold-componentions?

Nykyri,K.andMoore,T.W.andDimmock,A.P.andHenry,Z.

CentreforSpaceandAtmosphericResearch,Embry-RiddleAeronauticalUniversityIntheEarth'smagnetospherethespecificentropy,whichisameasureofnon-adiabaticheating,increasesby~twoordersofmagnitudewhentransitioningfrommagnetosheathintothemagnetosphere.However,theoriginofthisnon-adiabaticheatinghasnotbeenwellunderstood.Inaddition,thereexistsadawn-dusktemperatureasymmetryintheflanksoftheplasmasheet-thecoldcomponentionsarehotterby30-40%atthedawnsideplasmasheetcomparedtothedusksideplasmasheet.Ourrecentstatisticalstudyofmagnetosheathtemperaturesusing7yearsofTHEMISdataindicatesthationmagnetosheathtemperaturesdownstreamofquasi-parallel(dawn-flankforParker-SpiralIMF)bowshockareonly~15percenthigherthandownstreamofthequasi-perpendicularshock.Thisseedmagnetosheathtemperatureasymmetryexistinginthemagnetosheathisthereforeinadequatetocausetheobservedleveloftheplasmasheettemperatureasymmetry.Inthispresentationweaddresstheoriginofnon-adibaticheatingfrommagnetosheathintoplasmasheetbyutilizingsmallClusterspacecraftseparations,statisticalTHEMISdataaswellassimulations.Weshowhowfluid-scaleKelvin-Helmholtzwavescanradiateion-scalemagnetosonicmodeswhichinturnheattheionsthustransferringthekineticenergyoftheshockedsolarwindintoheatenergyofmagnetosphericions.ThestatisticalstudyoftheKelvin-Helmholtzwavesandion-scalewaveactivityshowsalsoadawnfavoredasymmetrywhichmayexplaintheobservedasymmetryincold-componentplasmasheetions.Thissamecross-scaleheatingmechanismmayplayrolealsoelsewhereintheuniversewheresignificantflowshearsarepresentsuchasinthesolarcoronaand

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otherastrophysicalplasmas.Themechanismmayalsoexplainhowtheelectrons'know'whenionshavebeenheated,alongstandingmysteryrelatedtoplasmasheettransport.

Kelvin-Helmholtzinstability:lessonslearnedfromCluster&Themisandwayforward

ArnaudMasson(1),C.PhilippeEscoubet(2),HarriLaakso(1)

(1)ESAC/ESA,SRE-O,Madrid,Spain(Arnaud.Masson@esa.int)(2)ESTEC/ESA,Noordwijk,TheNetherlands

Overmorethan10years,theClusterandtheThemismissionshaveshedatotalnewlightontheKelvin-HelmholtzInstabilitymechanism.Tonameafew,thesemissionshaveenabledtheobservationofKHIrolled-upvorticesforthefirstwithfourspacecraft(Hasegawaetal.,2004).TheyrevealeditspresenceunderanyIMFconditions(Hwangetal.,2011,2012),previouslyunderestimated(KavosiandRaeder,2015).Veryrecently,thepresenceofionmagnetosonicwaveswithsufficientenergytoaccountfortheobservedlevelofionheatingwithinaKHIvortexmaybeevidenceofcross-scaleenergytransport(Mooreetal.,2016).AfterpresentingsomethemainhighlightsofClusterandThemisonthisphenomenon,wewillpresentupcomingnewobservationswithCluster,ThemisandMMSforeseenin2019-2020timeframe.Nowlookingforward:howtogofromaqualitativepicturetoaquantitativepictureofthisphenomenon?Forinstance,howtoquantifytheroleofKHIintheformationofthecolddenseplasmasheet?Whichobservationswouldbethenneeded?Twomainconceptofnewobservationswillbeevoked.

ConjugacyofKelvin-HelmoltzInstabilityandPs6duringtheSt.Patrick'sDay2013MagneticStormEvent

MartinConnors

AthabascaUniversityObservatories

Ps6perturbationsareobservedprimarilyintheYandZcomponentsofthegroundmagneticfieldinthemorningsector,andaresometimesassociatedwiththeauroralformknownasomegabands.Theydriftsunwardataspeedcomparabletothe

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convectionspeed,andtheperturbationsareconsistentwithanequivalentcurrentclosingRegion1and2.Theassociationwithphaseofthesubstormremainscontentious,buttheyappeartobemoreprevalentunderstrongdrivingbythesolarwind.HeretheSt.Patrick'sDaystorm(March17-18)of2013isexaminedfortherelationshipofPs6toKelvin-HelmholtzwavespresentatthemagnetopauseasshownbyspacecraftcrossingsandbyMHDsimulations.ClusterandTHEMISconjunctionswiththegroundestablishacloseconnectionbetweenKHIonthemagnetopauseandPs6pulsations.KHIinspaceappearstolastlongerthancorrespondingPs6,andamplitudesarenotcloselyrelated.Interspacecraftcomparisonallowsthewavespeedtobefoundandcomparedtothatinsimulationsandofthepulsationsobservedontheground.

CharacterizationofenergeticO+andH+ionsintheplasmasheet

E.A.Kronberg(1,2),E.E.Grigorenko(3),P.W.Daly(1),H.Luo(4),Y.Khotyaintsev(5)

(1)MaxPlanckInstituteforSolarSystemResearch,Göttingen,Germany;(2)LudwigMaximilianUniversityofMunich,Germany;(3)SpaceResearchInstitute,RussianAcademyofSciences,Moscow,Russia;(4)KeyLaboratoryofIonosphericEnvironment,InstituteofGeologyandGeophysics,ChineseAcademyofSciences,

Beijing,China;(5)IRF,Uppsala,Sweden;

Thespatialdistributionsofdifferentionspeciesareusefulindicatorsforplasmasheetdynamics.BasedonClusterobservations,weestablishthespatialdistributionsofoxygenionsandprotonsatenergiesfrom274to955keV,dependingongeomagneticandsolarwind(SW)conditions.Comparedwithprotons,thedistributionofenergeticoxygenhasstrongerdawn-duskasymmetryinresponsetochangesinthegeomagneticactivity.ThestrongestchangesoftheionintensitiesareassociatedwithAEindexandnotthechangeoftheIMFdirectionorSWPdyn.Thehighoxygenintensitiesduringdecliningsolarcyclephaseassociatedwithhighsubstormoccurrenceareobserveddespitethefactthationosphericionoutflowisthestrongestduringthesolarmaximum.Werelateittotheeffectiveresonantaccelerationbyelectro-magneticfluctuationsatoxygengyrofrequenciesinthemagnetotailduringsubstorms.

ARTEMISobservationsofterrestrialionosphericmolecularionsattheMoon

A.R.Poppe1,2,M.O.Fillingim1,J.S.Halekas2,3,J.Raeder4andV.Angelopoulos5

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1SpaceSciencesLaboratory,UniversityofCalifornia,Berkeley,CA2SolarSystemExplorationResearchVirtualInstitute,NASAAmesResearchCenter,

MoffettField,CA3DepartmentofPhysicsandAstronomy,UniversityofIowa,IowaCity,IA

4SpaceScienceCenter,UniversityofNewHampshire,Durham,NH5DepartmentofEarthandSpaceSciences,andInstituteofGeophysicsand

PlanetaryPhysics,UniversityofCalifornia,LosAngeles,CARecently,Poppeetal.[2016]reportedonAcceleration,Reconnection,Turbulence,andElectrodynamicsoftheMoon'sInteractionwiththeSun(ARTEMIS)spacecraftobservationsofmultipleinstancesofoutflowingmolecularionosphericionsatlunardistancesintheterrestrialmagnetotail.Theheavyionfluxesareobservedduringgeomagneticallydisturbedtimesandconsistofmainlymolecularspecies(N2+,NO+,andO2+,approximatelymasses28-32amu)ontheorderof1e5-1e6/cm2/satnearlyidenticalvelocitiesasconcurrentlypresentprotons.Byperformingbackwardsparticletracingintime-dependentelectromagneticfieldsfromthemagnetohydrodynamicOpenGlobalGeospaceCirculationModel(OpenGGCM)oftheterrestrialmagnetosphere,theyshowedthattheionsescapetheinnermagnetospherethroughmagnetopauseshadowingnearnoonandaresubsequentlyaccelerateddown-tailtolunardistances.Here,weexpandupontheseobservationsbyinvestigatingthespatialdistributionofthemolecularionobservationsinthemagnetotailandbycorrelatingtimesofmolecularionobservationswithgeomagneticactivityandsolarwinddrivers.

Plasmasheetdriversofcurrentsandionosphericconductivityeffects

E.V.Panov,1W.Baumjohann,1R.A.Wolf,2R.Nakamura,1V.Angelopoulos,3J.M.Weygand,3M.V.Kubyshkina4

1SpaceResearchInstitute,AustrianAcademyofSciences,Graz,Austria.2PhysicsandAstronomyDepartment,RiceUniversity,Houston,Texas,USA.3InstituteofGeophysicsandPlanetaryPhysics,UCLA,LosAngeles,USA.

4InstituteofPhysics,St.PetersburgStateUniversity,St.Petersburg,RussianFederation.

ViolentreleasesofspaceplasmaenergyfromtheEarth'smagnetotailduringsubstormsproducestrongelectriccurrentsandbrightaurora.Butwhatmodulatesthesecurrentsandauroraandcontrolsdissipationoftheenergyreleasedintheionosphere?UsingdatafromtheTHEMISfleetofsatellitesandground-basedimagersandmagnetometers,weshowthatplasmaenergydissipationiscontrolledbyfield-alignedcurrents(FACs)producedandmodulatedduringmagnetotail

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topologychangeandoscillatorybrakingoffastplasmajetsat10-14Earthradiiinthenightsidemagnetosphere.

DistributionofRegion1and2currentsinthequietandsubstormtimeplasmasheetfromTHEMISobservations

JiangLiu,VAngelopoulos,XiangningChu,RLMcPherron

UCLA

AlthoughEarth'sRegion1and2currentsarerelatedtoactivitiessuchassubstorminitiation,theirmagnetosphericoriginremainsunclear.UtilizingthetriangularconfigurationofTHEMISprobesat8-12REdowntail,weseektheoriginofnightsideRegion1and2currents.Thetriangularconfigurationallowsacurlometer-liketechniquewhichdonotrelyonactive-timeboundarycrossings,sowecanexaminethecurrentdistributioninquiettimesaswellasactivetimes.OurstatisticalstudyrevealsthatbothRegion1and2currentsexistintheplasmasheetduringquietandactivetimes.Especially,thisisthefirstunequivocal,in-situevidenceoftheexistenceofRegion2currentsintheplasmasheet.FartherawayfromtheneutralsheetthantheRegion2currentslietheRegion1currentswhichextendatleasttotheplasmasheetboundarylayer.Atgeomagneticquiettimes,theseparationbetweenthetwocurrentsislocated~2.5REfromtheneutralsheet.ThesefindingssuggestthattheplasmasheetisasourceofRegion1and2currentsregardlessofgeomagneticactivitylevel.Duringsubstorms,theseparationbetweenRegion1and2currentsmigratestoward(awayfrom)theneutralsheetastheplasmasheetthins(thickens).ThismigrationindicatesthatthedeformationofRegion1and2currentsisassociatedwithredistributionofFACsourcesinthemagnetotail.InsomesubstormswhentheTHEMISprobesencounteradipolarization,asubstormcurrentwedge(SCW)canbeinferredfromourtechnique,anditshowsadistinctivelylargercurrentdensitythanthepre-existingRegion1currents.ThisdifferencesuggeststhattheSCWisnotjustanenhancementofthepre-existingRegion1current;theSCWandtheRegion1currentshavedifferentsources.

AcasestudyontheFACcarriersinthemagnetotailinsubstormtime

J.K.Shi1,Z.W.Cheng1,J.C.Zhang2,L.M.Kistler2,G.Parks3,M.Dunlop4,I.Dandouras5,H.Rame5,A.Fazakerley6

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1StateKeyLaboratoryofSpaceWeather,NSSC/CAS,Beijing,China2SpaceScienceCenter,UNH,Durham,NewHampshire,USA

3SpaceScienceLaboratory,UCBerkeley,USA4SSTD,RutherfordAppletonLaboratory,Didcot,Oxfordshire,UK5UniversityofToulouse,UPS,IRAP,andCNRS,Toulouse,France

6MSSL,UniversityCollegeLondon,London,UK

TheFACvariationsindicatenotonlydisturbancesofthemageticfield,butalsodynamicsofthechargedparticlesthosecanbenamedtheFACcarriers.Inthepolarregion,itiswellknowthattheFACcarriersaremainlytheprecipitationelectrons.However,inthemagnetotail,theFACcarriershavebeenpoorlyunderstood.TakingadvantageofmagneticfieldandplasmamultiinstrumentonbaordthefourClusterspacecraftastheycrossedtheplasmasheetboundarylayerinthemagnetotailinstormtimeon14September2006.WeidentifiedthespeciesandenergyrangeoftheFACcarriers,andanalyzeditscharacteristics.Theresultsindicatethat,inthesubstormtime,notonlytheelectronsfrom0.5to26keV,butalsotheenergetickeVionswerethemaincarriersfortheFAC.Theionswereoriginatedfromtheionospherethroughoutflowandwereacceleratedduringtransportation.ThisisthefirsttimewefoundtheionsalsocanbethemainFACcarriers.

Multi-pointstudiesoftheauroraandassociatedcavitybyCluster,andofBBFsandmagnetosheathjetsbyClusterandMMS

GoranMarklund(1),TomasKarlsson(1),LoveAlm(2),andPer-ArneLindqvist(1),

(1)\tSpaceandPlasmaPhysics,TheRoyalInstituteofTechnology,KTH,SE10044Stockholm,Sweden

(2)\tUniversityofNewHampshire,Durham,NH03824,USA

Resultswillbepresentedfrommulti-pointstudiesof(1)theauroralaccelerationregionandassociateddensitycavity,usingClusterdata,and(2)offastflowsinthemagnetotailandmagnetosheath,usingClusterandMMSdata.Inpart(1)therelativeroleofquasi-staticandAlfvenicaccelerationforproducinglarge-scaleauroralformsandsurges,andcharacteristicsoftheauroralcavityarediscussedbasedonnewresultsfromrecenteventandstatisticalstudies.Part(2)focussesbothonBurstyBulkFlowsinthemagnetotailandonjetsandplasmoidsinthemagnetosheath.ClusterandMMSdatafromdifferentpartsofthemagnetotailareusedtocalculatetheforcesactingontheBBFs,toexplorethefateoftheseastheyapproachEarth.Forthemagnetosheathjetsandplasmoids,theforcesactingonthesearecalculatedandassociatedwavesarestudied,whichmayprovidecluesaboutthefateofthejets,

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aswellasoftheirorigin.

Occurrenceofauroralomegabands

JamesM.Weygand,NooraPartamies,andLiisaJuusola

DepartmentofEarth,Planetary,andSpaceSciences,UniversityofCalifornia,LosAngeles

DepartmentofArcticGeophysics,TheUniversityCentreinSvalbard,Longyearbyen,Norway

FinnishMeteorologicalInstitute,HelsinkiFinlandOmegabandaurorahasbeendescribedasadiscretewaveformbetweentheregion-1andregion-2boundarydiffuseauroraboundarythatresemblestheGreekletteromega.Theseformsaregenerallyrelatedtoauroralactivityinthemorningsectorandduringsubstormrecoveryphase.Anumberofdetailedmulti-instrumentcasestudieshavebeenreportedonomegabandsbutveryfewstatisticalstudiesareavailable,suggestingthatomegaformsarenotcommoninauroraldisplays.MIRACLEall-skycameradatafromfiveLaplandstationsover1996-2007havebeensearchedforomegastructureswithanautomatedroutineandbyvisualinspection.Werequiredacleardiscretestructuretobepresentforeachomegabandwithalifetimeofmorethanaminute.Wealsorequiredthattheomegabandtobetallerthanwiderandthattheomegabandpropagatedeastward.Wefound458omega-likestructuresintotal,mostofthematthesouthernpartoftheauroraloval,inthefield-of-viewofSodankylacamera.Alltheomegasoccurredafterasubstormonsetandmostofthemduringarecoveryphase.ThesubstormswithomegabandswerefoundtobemoreintensethanaveragesubstormswithintheLaplandregion.Furthermore,theomegaoccurrenceratepeakedbetween2002and2004duringthedecliningphaseofthesolarcycle.Theomegabandwave-likeundulationwasobservednotonlyintheopticaldatabutalsointheequivalentcurrentdistribution.OmegaformsoccurredinbetweentheRegion1and2currentsnearthediffuseauroraboundary,andwithinawestwardelectrojetcurrent,whichappearedstrongerthanthatofaveragesubstormwestwardelectrojetintheLaplandregion.ForasmallfractionoftheomegabandeventsnearconjugatespacecraftdatawereavailableandthesedatashowedfastEarthwardflowsinthemagnetotailexceptforoneeventthatdisplayednohighspeedflows.Wediscussapossiblescenarioofomegaformationandtherelativeoccurrenceoftheomegabands.

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Statisticalpropertiesofsubstormauroralonsetbeads/rays

ToshiNishimura1,JianYang2,PhilPritchett3,FerdinandCoroniti3,EricDonovan4,LarryLyons1,RichardWolf2,VassilisAngelopoulos5,StephenMende6

1DepartmentofAtmosphericandOceanicSciences,UniversityofCalifornia,Los

Angeles,LosAngeles,California,USA2DepartmentofPhysicsandAstronomy,RiceUniversity,Houston,Texas,USA3DepartmentofPhysicsandAstronomy,UniversityofCalifornia,LosAngeles,

California,USA4DepartmentofPhysicsandAstronomy,UniversityofCalgary,Calgary,Alberta,

Canada5DepartmentofEarth,PlanetsandSpaceSciences,UniversityofCalifornia,Los

Angeles,LosAngeles,California,USA6SpaceScienceLaboratory,UniversityofCalifornia,Berkeley,Berkeley,California,

USAAuroralsubstormsareoftenassociatedwithopticalrayorbeadstructuresduringinitialbrightening(substormauroralonsetwaves).Occurrenceprobabilitiesandpropertiesofsubstormonsetwaveshavebeencharacterizedusing112substormeventsidentifiedinTHEMISall-skyimagerdata,andcomparedtoRiceConvectionModel-Equilibrium(RCM-E)andkineticinstabilityproperties.CasestudieswerealsoperformedwiththeconjugateTHEMISsatellitesintheplasmasheet.Allsubstormonsetswerefoundtobeassociatedwithopticalwaves,andthusopticalwavesareacommonfeatureofsubstormonset.Eastward-propagatingwaveeventsaremorefrequentthanwestward-propagatingwaveevents,andtendtooccurduringlower-latitudesubstorms(strongersolarwinddriving).Thewavepropagationdirectionsareorganizedbyorientationofinitialbrighteningarcs.Wealsoidentifiednotabledifferencesinwavepropagationspeed,wavelength(wavenumber),periodanddurationbetweenwestwardandeastwardpropagatingwaves.Incontrast,thewavegrowthratedoesnotdependonthepropagationdirectionorsubstormstrengthbutisinverselyproportionaltothewaveduration.Thissuggeststhatthewavesevolvetopolewardexpansionatacertainintensitythreshold,andthatthewavepropertiesdonotdirectlyrelatetosubstormstrengths.However,wavesarestillimportantformediatingthetransitionbetweenthesubstormgrowthphaseandpolewardexpansion.TherelationtoarcorientationcanbeexplainedbymagnetotailstructuresintheRCM-E,indicatingthatsubstormonsetlocationrelativetothepressurepeakdeterminesthewavepropagationdirection.Themeasuredwavepropertiesagreewellwithkineticballooninginterchangeinstability,whilecross-fieldcurrentinstabilityandelectromagneticioncyclotroninstabilitygivemuchlargerpropagationspeedandsmallerwaveperiod.

Theionosphereasginormousparticledetector

51

JoshuaSemeter,NithinSivadas,HassanAkbari,MichaelHirsch,JohnSwoboda

BostonUniversityTheformationofplasmabeamsisaubiquitousconsequenceofenergypropagationthroughamagnetizedplasma.Withingeospace,thebeamenergyisultimatelydissipatedasheat,light,ionization,andturbulenceintheouteratmosphere.Carefulobservationofthecombinedresponseprovidesaremarkablyversatileremotesensingdiagnosticforthelocationandmechanismofparticleenergization.Thispaperreviewsrecentresearchonbeam-ionosphereinteractions,withapplicationtounderstandingspace-timedynamicsofthedisturbedmagnetosphere.Selectcasestudiesinvolvingcollaborativemeasurementsfromspace(predominentlyusingtheTHEMISconstellation)andground(PFISR/RISRandcollocatedauroralimagingsystems)havebeenusedtoinvestigatethepartitioningofbeamenergizationmechanismsduringreconnectionandsubstormintervals.Theresultsshedlightonthenatureofenergytransferinthegeospacesystem.

TREx-anASIandRiometernetworkdesignedtotakeTHEMIS-ASI'tothenextlevel

EricDonovan

UniversityofCalgaryTHEMIS-ASIhashadatransformativeimpactonourunderstandingofgeospacedynamics.WithtimesequencesofmosaicsstitchedtogetherfromimagesfrommultipleASIswithoverlappingfieldsofview,usedincoordinationwithinsitudatafromTHEMISandothermissions,wehavediscoverednewmodesofcouplingingeospace,broughtourselvestantalizinglyclosetounderstandingthesubstormonsetmechanism,andsignificantlyadvancedourunderstandingoftheaurora.Thishasbeenafantasticprogram,buttherearelimitations.Becausetheimagesarepanchromatic(whitelight),andthecadenceis3seconds,welackinformationontheenergyoftheprecipitatingelectrons,andthingsthathappenonthesecondtimescalearejustoutofourview.TRExisanewlyfundedCanadiannetworkdesignedtoaddnewcapabilitiesontopofTHEMIS-ASItoaddressthelackofenergyinformationandthe3(6)secondlimitontemporalresolution.TRExisisbeingdeployedoverthenexttwoyears,andwillconsistofsixopticalimagingstations,eachhavingfourASIs.ThesewillbeafullcolorequivalenttoaTHEMIS-ASI,andthreenarrow-bandimagerstargetingemissionsinthenearinfrared(NIR),blueline(N2+),andredline(630nm).Thecombinedfieldofviewwillalsobecoveredbytenimagingriometers.Theriometers,NIR,andfull-colorASIsandtheimagingriometerswilloperateat3secondcadence,timedwithTHEMIS-ASI,andthebluelineASIswillimageatupto30Hz.The

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observationalobjectiveistocreatetwo-D,time-evolvingmapsofcharacteristicenergy,totalenergyflux,andtimefrequencydomaininformationupto15Hz.InthistalkIwilloutlinethescientificdevelopmentsthatledustorecognizetheneedforTREx,andoutlinesomeoftheexcitingsciencewebelievethisnewfacilitywillsupport.

DeterminationofdynamicsofturbulenceupstreamanddownstreamoftheEarth'sBowshock,usingClustermeasurements

StefanosGiagkiozis,SimonN.Walker,KeithYearby

UniversityofSheffieldCollisionlessshocks(CS)areoftenaccompaniedbyturbulencebothupstreamanddownstreamofthemainramp.Thisturbulenceiscloselyrelatedwiththeformationoftheshockandthereforewiththedissipationofsolarwindflowtothermalenergy.InordertounderstandtherelationofthesewavestotoCS,wefirstneedtodeterminetheiroriginanddynamics.Multi-spacecraftmeasurementscanbeusedincombinationwithtimeandfrequencytechniques,inordertodeterminethepropagationdirectionofthesewavesandtheirnon-lineardynamics.TheClustercloseseparationcampaignallowstheinvestigationofwaveswithsmallerwavelengths,usingtimeandfrequencydomaintechniques.MagneticfieldmeasurementswillbeexaminedinthetworegionsoneachsideofthemainrampoftheBowShock.Thepropagationvectormagnitudeanddirectionwillbedeterminedalongwiththenon-lineardynamicsofthewaves.

RapidchangesinthesolarwindprotonvelocitydistributionfunctionobservedwithCIS

O.Roberts1

X.Li2D.Perrone3C.PEscoubet1

1ESTEC,Noordwijk,Netherlands

2AberystwythUniversity,Wales,UK3ESAC,Madrid,Spain

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Thecollisionlessnatureofthesolarwindplasma,aswellastheabilitytosupportanumberofwavesandcoherentstructures,giverisetoanumberofnon-Maxwellianfeaturesinthevelocitydistributionfunction.UsingobservationsofthefullthreedimensionaldistributionsfromtheClusterIonSpectrometertheVDFisseentochangesignificantlyontimescalesofminutes.Insomeinstancesdoublecoresofthevelocitydistributionfunctioncanbeseen.Usingwaveletanalysisthepropertiesofthemagneticfieldfluctuations(coherency,phase,power)canbeobtainedattheinstanttheVDFissampled.Additionallymulti-spacecrafttimingcanalsohelpcharacterisefluctuationsanddeterminewhethercoherentstructurescontributetotheshapeoftheVDF.

Variabilityoftheelectronpowerspectruminthesolarwind

O.Roberts1A.Walsh2

C.P.Escoubet1P.Kajdic3

1ESTEC,Noordwijk,TheNetherlands

2ESAC,Madrid,Spain3UniversidadNacionalAutÃnomadeMéxicoInstitutodeGeofÃsica

Atsubionscalestheslopeandmorphologyoftheturbulencepowerspectrumisatopicofopendebate.Ashortintervalofsolarwindmagneticfielddatasampledat450HzbyCluster'sStaffinstrumentwheninburstmodeshowthepresenceofsporadicshortdurationenergeticevents,whichlastforafewsecondswithinaminuteinterval.Waveletcoherenceandphasebetweencomponentsintheplaneperpendiculartothemagneticfieldsuggestthatthesefluctuationsarewhistlerwaves.Althoughtheyonlycovermakeupt10%ofthetimetheyareclearlyvisibleintheglobalpowerspectraldensity.Electrondistributionssampledshowthepresenceoftwobeamsduringthemostintenseemission.Thesourceofthesefluctuationsisunclearsincetheelectronmomentssuggesttheplasmaisstablewithrespecttothewhistleranisotropyinstabilityandtheelectronheatfluxinstability.

Turbulenceintheterrestrialforeshock:Multipointobservations

A.Pitna,J.Safrankova,Z.Nemecek

CharlesUniversity,FacultyofMathematicsandPhysics,Prague,CzechRepublicManylinearandnon-linearprocessesconnectedwithareflectionofsolarwindparticlestakeplaceinaforeshock,theregionupstreamoftheEarthbowshock.

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Whenthebowshockisquasiparallel,thisregioncanextenduptomanyEarth'sradii.Undersuchcondition,theincidentsolarwindisstronglydisturbedandphysicalfields(velocityandmagneticfields),Q,fluctuateconsiderably,sothatdeltaQ/Q~1.Theserelativefluctuationsofparametersarewelllocalized,eitherinfrequencyorinspace.Nevertheless,originalbackgroundsolarwindturbulenceshouldbestillpresent,maybewithaloweramplitude.Multipointobservationsintheforeshockallowustomapforeshockstructuresfromsmalltolargespatialscales.WeemploymeasurementsoftheBMSWinstrumentonboardtheSpektr-Rspacecraftwitha32msresolutionoftheionflux,density,andbulkandthermalspeedsandcomparetheresultsoftheirspectralanalysiswithasimilaranalysisinthepristinesolarwind(Windat~1AU)andwithobservationsofthespacecraftorbitingneartheEarth(Cluster,THEMIS).

MagneticCurvatureAnalysisonKelvin-HelmholtzWaves:aMHDSimulationStudy

R.Kieokaew(1),C.Foullon(1),B.Lavraud(2)

(1)CentreforGeophysicalandAstrophysicalFluidDynamics,Mathematics,UniversityofExeter,UK

(2)InstitutdeRechercheenAstrophysiqueetPlanétologie,UniversitédeToulouse,Toulouse,France

Four-spacecraftmissionsareprobingtheEarth'smagnetosphericenvironmentwithhighpotentialforrevealingspatialandtemporalscalesofavarietyofin-situphenomena.Magneticcurvaturesareintrinsictocurvedmagneticfieldswherethemagneticenergyisstoredintheformofmagnetictension.In-situmagneticcurvatureshavebeenresolvedbythefour-spacecrafttechniquecalled'magneticcurvatureanalysis'(MCA).TheMCAtechniquehasbeenusedinvariousplasmastructuresidentifiedascurrentsheets,plasmoids,andmagneticreconnectiondiffusionregions.Weinvestigatetherobustnessofthemethodtointerpretapplicationsintherealdata.Here,forthefirsttime,wetesttheMCAona2.5DMHDsimulationofcurvedmagneticstructuresinducedbyKelvin-Helmholtz(KH)waves.Increasing(regular)tetrahedronsizesofvirtualspacecraftareusedtomeasurethecurvaturesofKHvortices.WeinvestigatethemagnetopausecurvaturefortwomainlocationsofKHvortexandweproducetimeseriescorrespondingtothesepositions(forstaticspacecraftintheboundarylayers).Wehavefoundvariationsofthecurvaturevectorsbothinradiiandorientationsdependingonthesizesofthetetrahedron.ThisishelpfultobetterunderstandtheMCAmeasureswhenthetechniqueisappliedtoin-situdatawithoutknowingthescalesizesofplasmastructuresunderconsideration.Thisstudylendssupportforcross-scale

55

observationstobetterunderstandthenatureofcurvatureanditsroleinplasmaphenomena.

Kelvin-HelmholtzwaveatthesubsolarmagnetopauseboundarylayerunderradialIMF

K.Grygorov(1),Z.Nemecek(1),J.Safrankova(1),L.Prech(1),G.Pi(2),J.-H.Shue

(2)

(1)CharlesUniversity,FacultyofMathematicsandPhysics,VHolesovickach2,18000Prague8,CzechRepublic,(2)NationalCentralUniversity,InstituteofSpace

Science,300JhongdaRoad,Jhongli,Taoyuan32001,Taiwan.WepresentthefirstobservationoftheKelvin-Helmholtz(KH)rolled-upvortexatthedaysidemagnetopauselayersunderaradialinterplanetarymagneticfield(IMF).ThestudyusesmeasurementsoffourTHEMISprobesalignedalongtheYaxisabout10ReupstreamoftheEarthandlocatedindifferentregionsofthenear-Earthenvironment.THEMISCandAserveasmonitorsofthequietsolarwindandfluctuatingmagnetosheathconditions,respectively,andTHEMISDandEobservethemagnetopauseandlow-latitudeboundarylayer(LLBL)crossings.Theanalysisshows:(1)aradialIMFchangestothesouthwardpointingmagnetosheathmagneticfield;(2)daysidereconnectionformsthethinbutdenseLLBL;(3)alargevelocityshearattheLLBLinneredgeexcitesatrainofKHwaves;and(4)inspiteofashortpathfromthesubsolarpoint(5Re),oneofKHwavesexhibitsallfeaturesofafullydeveloperrolled-upvortex.

Shapeofthedaysideequatorialmagnetopause

J.Safrankova(1),J.Simunek(2),Z.Nemecek(1),andL.Prech(1)

(1)CharlesUniversity,FacultyofMathematicsandPhysics,VHolesovickach2,18000Prague8,CzechRepublic,(2)InstituteofAtmosphericPhysics,CzechAcademyof

Sciences,BocniII1401,14131Prague4,CzechRepublic.Amagnetopauselocationisgenerallybelievedtobedeterminedbythesolarwinddynamicpressureandbyasignandvalueoftheinterplanetarymagneticfieldvertical(Bz)component.Thecontributionofotherparametersisusuallyconsideredtobeminorornegligibleneartheequatorialplane.Agreatmajorityofpresentmagnetopausemodelsdescribesthemagnetopauseshapewithanellipsoidorparaboloidofrevolution.TheaxisofsuchsurfaceusuallyreflectstheEarthorbitalmotionaroundtheSun.Tenyearsofmagnetopauseobservationsnearthe

56

equatorialplanebytheTHEMISspacecraftallowtotestsofthisdescriptionandfacilitatessearchforabetterapproximationofthemagnetopauseshape.Wepresentastatisticalstudybasedonmorethan10.000magnetopausecrossingsidentifiedintheTHEMISdata.Thestudyaccountsforthedependenceofthemagnetopauselocationontheupstreamsolarwinddynamicpressureandexpectsthatallothereffectscanbeaveraged.Thestudysuggestsaverysimpleexpressionfortheshapeofthedaysidemagnetopauseandexaminestheinfluenceofinterplanetarymagneticfieldandsolarwindparametersonthisshape.Theeffectsofthemagnetosphericcurrentsystemsarediscussed.

Newtoolsformulti-missiondataanalysiswithCluster:SPEDAS,OVTandCSA2.0

HelenMiddleton,ArnaudMassonandtheCSADevelopmentTeam

ESAC,MadridTheClusterScienceArchive(CSA)isthelongtermdatarepositoryofallbest-qualityClusterdataforthescientificcommunity.ItisheldandmanagedatESAC,Madridandiscontinuouslyupdated(currentlyat~100TB).Twomethodscurrentlyexisttoaccessthesedata:throughthecommandline(scripts,etc)andthroughaJavagraphicaluserinterface(GUI).Whilemostdataisdownloadedviathecommandline,theGUIoffersmanyextrastoquicklybrowsedata,likeon-demandandpre-generatedgraphicalproducts,particledistributionfunctionsanddatainventoryplots.Asubstantialamountofdocumentationisavailableforthecommunitytobestusethevariousdatasetsoffered(cosmos.esa.int/csa).Fordatavisualization,theSpacePhysicsEnvironmentDataAnalysisSoftware(SPEDAS)enablesClusterdatatobedisplayedalongsidethatofMMS,THEMIS,VanAllenProbesandsoon,ERG.SPEDASisaframeworkabletodownloadandvisualiseinparticularCDAWebdatawhichincludesClusterdatainCDFforspinresolution(FGMdataareavailableuptosummer2016)andWBD;primeparametersforalltheotherdatasets.Theinclusionofallbest-resolutionCSAdatawithinCDAWebison-going.Anewversionofthe3DOrbitVizualisationTool(OVT)wasreleasedinApril2016.DevelopedbyIRF(Uppsala,Sweden),itnowenables3Dvisualisationofsimultaneousorbitsandmagneticfootprintsfromvarioussatellites,thankstoadirectlinktotheNASA'sSatelliteSituationCenter.Thisallowsuserstofindconjunctionsandsuitableoverlappingdatasetsincontext.CSA2.0iscurrentlyindevelopment,expectedtobereleasedtothepublicin2017.Itconsistsofawebinterfacewhichdoesn'trequireaprogramtobedownloadedanymore;itwillworkdirectlyfromanybrowser.Thiscrisp,clean,newinterfacewill

57

offerallthecurrentlyavailableservicesplusmore,includingaDataMiningsearchtool.Thistoolwillallowdatatobefoundnotonlybytimeperiodsbutalsobyphysicalparametersandregion-specificcriteria.

CorrectingtheRAPIDImagingElectronSpectrometerdatasetforlong-termsensitivitydecrease

E.Vilenius,P.Daly,E.Kronberg

MaxPlanckInstituteforSolarSystemResearch

TheClustermissionhasbeenoperationalformorethan16years.Analysisoflong-termdatasetsfromtheRAPIDinstrumentshowsignsofdegradedsensitivityoverrecentyearsinthe3DdatafromtheImagingElectronSpectrometer(IES).Thisdegradationisarelativeeffectseenwhencomparingthe9detectorsofIES,eachlookingintodifferentpolardirectionandcoveringanangleof20degrees.Thiseffectisanearlysymmetricdecreaseofsensitivityasafunctionofdetectornumbersothatthemiddledetectorsareaffectedthemost.Thislong-termdecaystartedin2007inallthefourRAPIDinstrumentswithadropinsensitivityofdetectors2-8comparedtodetectors1and9(thelattertwoarelookingalmostparallelandanti-paralleltothespinaxis).Thisdecreasingtrendstabilizedin2009-2010followedbyanotherdropin2012.Herewepresenttheresultsoftheprocessofdeterminingcorrectionfactorsfortherelativelong-termeffect.Usingburstmodedata,thecorrectionfactorshavebeendeterminedindependentlyforeachenergychannelanddetector(2-8)relativetothemeanlevelofdetectors1and9whichareconsideredasabaseline.WehavevalidatedthecorrecteddatasetusingacollectionofallE2DD6data(nominalmode,9polardirectionsand6energychannels)abovetheradiationbelts(>7Re),sothateachdatapointinouranalysisistheaveragedifferentialfluxoveroneorbitandoneenergychannel.ThecorrecteddatasetwillbeavailableintheClusterScienceArchiveinthenearfuture.

Statisticalsurveyofquasi-periodicVLFemissionsobservedintheinnermagnetosphereconjugatedwithgeomagneticfieldfluctuationsmeasuredon

theground.

M.Hajos(1)O.Santolik(1,2)F.Nemec(2)

A.Demekhov(3,4)

58

M.Parrot(5)T.Raita(6)

1-InstituteofAtmosphericPhysics,CAS,Prague,Czechia.

2-FacultyofMathematicsandPhysics,CharlesUniversityinPrague,Prague,Czechia.

3-PolarGeophysicalInstitute,Apatity,RussianFederation.4-InstituteofAppliedPhysicsRAS,NizhnyNovgorod,RussianFederation.

5-LPC2E/CNRS,Orleans,France.6-SodankylaGeophysicalObservatory,UniversityofOulu,Sodankyla,Finland.

Wepresentacomparisonbetweenpropertiesofquasiperiodic(QP)ELF/VLFemissionsobservedbythelow-altitudeDEMETERspacecraftandULFgeomagneticfieldpulsationsmeasuredonthegroundbytheTHEMIS/CARISMA(CanadianArrayforRealtimeInvestigationsofMagneticActivity)systemofflux-gatemagnetometersandbytheSodankylaGeophysicalObservatory(SGO)magnetometer.Wehaveselectedforanalysisabout400QPDEMETEReventswhichwereconjugatedwithground-basedstations.TheanalyzedQPeventshavemodulationperiodslargerthan10sandfrequencybandwidthshigherthan200Hz.AgoodagreementbetweenmodulationperiodsofQPemissionsandfrequenciesofthemostintensefluctuationsofULFpulsationshasbeenfoundforQPeventswithmodulationperiodslargerthan40s.SuchQPemissionswhichappeartobecloselyassociatedwithcoincidentgeomagneticpulsationsarecalledQP1,representingabout18percentsofthetotalnumberofanalyzedQPevents.Nocorrespondinggeomagneticpulsationswereidentifiedintheremaining82percentsofQPevents,andtheseeventsareclassifiedasQP2.ThemaximumspectralintensityofQP1eventsdoesnotseemtodependontheintensityofgeomagneticfieldfluctuationswhileQP2eventsintensityisincreasingwithintegralintensityofthegeomagneticfieldfluctuationsatfrequencies10-500mHz.TheintensityofgeomagneticfielddisturbancesgraduallyincreaseswithinvariantgeomagneticlatitudesduringQPemissionsofbothtypes.However,inthecaseofQP2type,arapidriseofgeomagneticfieldfluctuationswasobservedinthelatituderangeof60to65degrees.BasedontheobservedassociationbetweenQPemissionsandgeomagneticfielddisturbances,weattempttoestimatethespatialextentoftheQPemissionsandwediscusstheeffectofULFpulsationsofdifferentoriginonQP1emissionsinthemagnetosphere.

Multipointobservationsoflong-lastingPc4pulsationsinthedaysidemagnetosphere

G.I.Korotova1,2,D.G.Sibeck3,M.J.Engebretson4,J.R.Wygant5,S.Thaller5,H.E.

Spence6,C.A.Kletzing7,V.Angelopoulos8,R.J.Redmon9

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1IPST,UniversityofMaryland,CollegePark,MD,USA2IZMIRAN,RussianAcademyofSciences,Moscow,Troitsk,Russia

3Code674,NASA/GSFC,Greenbelt,MD,USA4AugsburgCollege,Minneapolis,MN,USA

5UniversityofMinnesota,Minneapolis,MN,USA6EOS,UniversityofNewHampshire,Durham,NH,USA

7IowaUniversity,IowaCity,IA,USA8UCLA,CA,USA

9NGDC/NOAA,Boulder,CO,USA

WeusemagneticfieldandplasmaobservationsfromtheVanAllenProbes,THEMISandGOESspacecrafttostudythespatialandtemporalcharacteristicsoflong-lastingpoloidalPc4pulsationsinthedaysidemagnetosphere.ThemoststrikingfeatureofthePc4pulsationswastheiroccurrenceatsimilarlocationsduringsuccessiveorbits.Weusedthisinformationtostudythelatitudinalnodalstructureofthepulsationsanddemonstratedthatthelatitudinalextentofthemagneticfieldpulsationsdidnotexceed2Earthradii(RE).Wefoundnodirectrelationshipbetweentheplasmapauseandthelong-lastingPc4pulsations.Wedemonstratedthatthelatitudinalnodalextentofthemagneticfieldpulsationsdidnotexceed2RE.WeinvestigatedthespectralstructureofthePc4pulsations.Wefoundthatthedominantperiodsinthespectradependedonorbitandradialdistance.

InfluenceofaguideBYfieldonthemagnetotailcurrentsheetstructureandparticledynamics

E.E.Grigorenko,A.Yu.Malykhin,H.V.Malova,L.M.Zelenyi

SpaceResearchInstituteofRAS,Moscow,Russia,MoscowInstituteofPhysicsandTechnology,Moscow,Russia,SkobeltsynInstituteofNuclearPhysics,MoscowState

University,Moscow,Russia

ThemagnetotailCurrentSheet(CS)playsakeyroleinthedynamicsoftheEarthmagnetosphere.Usually,themagneticfieldlines,crossingthemagnetotailequatorialplane,haveanormalcomponentBZduetotheEarth'sdipolefieldandasmallercomponentalongthedawn-duskdirection,BY.Sometimes,however,theBYcomponentinthemagnetotailCSbecomessignificantAstrongBYfieldcanshearthemagneticfieldoftheCSmakingtheCSthinandcausingacross-tailfield-alignedcurrent,influencingtheadiabaticityandorbitsofchargedparticlesintheCS,that,inturn,mayaffecttheCSstructureandstability.Thus,itisimportanttoknowthespatialdistributionoftheBYfieldacrosstheCSaswellasthecharacteristicscaleoftheCSregionwherethiscomponentdominates.Thisknowledgeistightlyconnectedwiththeunderstandingofmechanisms,whichareresponsibleforthestrongBY

60

fieldgenerationinthemagnetotailCS.TheBYcomponentinthemagnetotailmayexistduetothedirectpenetrationoftheinterplanetarymagneticfield(IMF).However,atsomeperiodsthestrengthoftheBYcomponentcanbeenhancedatthecenteroftheCSrelativetothatintheCSboundaries,sothatthespatialprofilesoftheBYcomponentalongthenorth-southdirectionhavea'bell-like'shape.ThemechanismoftheBYfieldenhancementinthecenteroftheCSisstilldebated.InthisworkweperformedtestionsimulationsinathinCSwiththeinitiallysmallguideBYfieldoriginatedfromtheIMFBYpenetrationintothemagnetotail.WeshowthepossibilityoftheBYfieldenhancementinthecenteroftheCSandformationofa'bell-shaped'BYfieldprofileduetotheinfluenceofthenonadiabaticionsontheCSstructure.WealsodiscussthekineticfeaturesofthenonadiabaticiondynamicsleadingtotheenhancementofthecoreBYfieldintheCSofplasmoids.

Substructureswithinadipolarizationfrontrevealedbyhigh-temporalresolutionClusterobservations

Yao,Zhonghua;Fazakerley,AN;Varsani,A;Rae,IJ;Owen,CJ;Pokhotelov,D;Forsyth,

C;Guo,RL;Bai,SC;Yao,ST;Doss,N

MullardSpaceScienceLaboratory,UniversityCollegeLondon,London,UK,SchoolofEarthandSpaceSciences,PekingUniversity,Beijing,China,

ShandongProvincialKeyLaboratoryofOpticalAstronomyandSolar-TerrestrialEnvironment,SchoolofSpaceScience

andPhysics,ShandongUniversity,Weihai,ChinaTheDipolarizationFront(DF),usuallyobservedneartheleadingedgeofaBurstyBulkFlow(BBF),isthoughttocarryanintensecurrentsufficienttomodifythelarge-scalenear-Earthmagnetotailcurrentsystem.However,thephysicalmechanismofthecurrentgenerationassociatedwithDFsispoorlyunderstood.Thisisprimarilyduetothelimitationsofconventionalplasmainstrumentswhichareunabletoprovideasufficientnumberofunaliased3DdistributionfunctionsonthetimescaleoftheDF,whichusuallytravelspastaspacecraftinonlyafewseconds.ItisthusalmostimpossibletounambiguouslydeterminethedetailedplasmastructureoftheDFattheusualtemporalresolutionofsuchinstruments.HerewepresentdetailedplasmameasurementsusingtheClusterPEACEelectronandCIS-CODIFiondataforaneventduringwhichitwaspossibletoobservethefullpitchangledistributionatacadenceof1/4second.Theobservationsclearlyshowdetailsofplasmasub-structurewithintheDF,includingthepresenceoffield-alignedelectronbeams.Inthisevent,thecurrentdensitycarriedbytheelectronbeamismuchlargerthanthecurrentobtainedfromthecurlometermethod.Wealsosuggestthatthefield-alignedcurrentaroundtheDFobtainedfromthecurlometermethodmayhavebeenmisinterpretedinpreviousstudies.Ourresultsimplythatthenature

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oftheDFcurrentsystemneedstoberevisitedusinghighresolutionparticlemeasurements,suchasthoseobservationsshortlytobeavailablefromtheMagnetosphericMultiscale(MMS)mission.

Temporalandspatialevolutionofmagnetotaildipolarizationfrontsinthenear-Earthplasmasheet

D.Schmid,R.Nakamura,F.Plaschke,M.VolwerkandW.Baumjohann

SpaceResearchInstitute,AustrianAcademyofSciences,A-8042Graz,Austria

Dipolarizationfronts(DFs)playacrucialrolefortheenergyandmagneticfluxtransportinthemagnetotail.Theyarecharacterizedbyarapidincreaseinthenorthwardmagneticfieldcomponentperpendiculartothecurrentsheet(Bz),whichistypicallyprecededbyatransientdecrease,theBz-dip.Wepresentastatisticalstudyonthetemporal/spatialevolutionoftheDFsandtheirBz-dipsastheypropagateEarthward.WeusemagnetotailobservationsfromtheMagnetosphericMultiscale(MMS)missionduringthecommissioningphasewhenMMShadastring-of-pearlsconfigurationatradialdistanceswithin12Reandinter-spacecraftdistancesof100km.Thisparticularspacecraftconstellationenablesustostudythetemporal/spatialevolutionofDFsonasmallscaleinthenear-Earthplasmasheet.ThemainaimofthisstudyistorevealtheevolutionofDFsclosertotheflowbrakingregion,inordertobetterunderstandthemagneticfluxtransportinthemagnetotail.

Comparingandcontrastingdispersionlessinjectionsatgeosynchronousorbitduringasubstormevent

E.A.Kronberg(1,2),E.E.Grigorenko(3),D.L.Turner(4),G.Reeves(5),

P.W.Daly(1),Y.Khotyaintsev(6)

(1)MaxPlanckInstituteforSolarSystemResearch,Göttingen,Germany;(2)LudwigMaximilianUniversityofMunich,Germany;(3)SpaceResearchInstitute,RussianAcademyofSciences,Moscow,Russia;(4)TheAerospaceCorporation,El

Segundo,USA;(5)LANL,LosAlamos,USA;(6)IRF,Uppsala,SwedenParticleinjectionsinthemagnetospheretransportelectronsandionsfromthemagnetotailtotheradiationbelts.Here,weconsidergenerationmechanismsof``dispersionless''injections,namelythosewithsimultaneousincreaseoftheparticlefluxoverawideenergyrange.Inthisstudywetakeadvantageofmulti-satelliteobservationswhichsimultaneouslymonitorEarth'smagnetosphericdynamicsfromthetailtowardstheradiationbelts

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duringasubstormevent.Dispersionlessinjectionsoccuratthesubstormgrowthphaseassociatedwithinstabilitiesintheplasmasheetandattheonset/expansionphaseassociatedwithmultipledipolarizationfronts.Theyshowdifferentspatialspreadandthepropagationmanner.Atthedistanceforgeosynchronousorbit(6.6RE),theelectrondistributionsdonothaveaclassicpowerlawfitbutinsteadabump-on-tailcenteredon~120keVduringdispersionlesselectroninjections.However,electrondistributionsofinjectionsassociatedwithdipolarizationsinthemagnetotail(13RE)donotshowsuchasignature.Wesurmisethatanadditionalresonantaccelerationoccursin-betweentheselocations.Werelatetheaccelerationmechanismtotheelectrondriftresonancewithultralowfrequency(ULF)waveslocalizedintheinnermagnetosphere.

IMFdependenceofenergeticoxygenandhydrogeniondistributionsinthenear-Earthplasmasheet

H.Luo(1,2,6),E.A.Kronberg(2,3),K.Nykyri(4),K.J.Trattner(5),P.W.Daly(2),G.X.

Chen(1,6),A.M.Du(1,6)

1KeyLaboratoryofEarthandPlanetaryPhysics,InstituteofGeologyandGeophysics,ChineseAcademyofSciences,Beijing,100029,China

2MaxPlanckInstituteforSolarSystemResearch,Göttingen,37077,Germany3DepartmentofEarthandEnvironmentalSciences,Ludwig-MaximiliansUniversity,

Munich,80333,Germany.4CentreforSpaceandAtmosphericResearchandDepartmentofPhysicalSciences,

Embry-RiddleAeronauticalUniversity,DaytonaBeach,Florida,USA5LASP,UniversityofColoradoBoulder,Boulder,ColoradoUSA

6UniversityofChineseAcademyofSciences,Beijing,100049,China

Energeticiondistributionsinthenear-Earthplasmasheetcanprovideimportantinformationforunderstandingtheentryofionsintothemagnetosphere,andtheirtransportation,acceleration,andlossesinthenear-Earthregion.Inthisstudy,11yearsofenergeticprotonandoxygenobservations(>~100keV)fromCluster/RAPIDwereusedtostatisticallystudytheenergeticiondistributionsinthenear-Earthplasmasheet.Thedawn-duskasymmetriesofthedistributionsinthreedifferentregions(daysideplasmasheet,near-Earthnightsideplasmasheet,andtailplasmasheet)areexaminedinnorthernandsouthernhemispheres.ResultsshowthattheiondistributionasymmetriesintheplasmasheetarehighlydependentontheIMFclockangle.Thedawn-duskasymmetriesseemtobedeterminedbylocationofmagneticreconnectionatthemagnetopauseforbothnorthernandsouthernhemispheres.Theresultsgiveanimplicationthatthesourceofenergeticions(higherthanafewhundredkeV)inthenearEarthplasmasheetcanbethecuspand/orquasi-parallelbowshockandnotonlythesubstorm-relatedprocessesinthe

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magnetotail.WeshowthattheinfluenceoftheIMFclockangleonthedistributionsoftheenergeticprotonsandoxygeninthenear-Earthplasmasheetshouldnotbeneglectedinmodeling.

Amulti-satellitesurveyofconvectionintheterrestrialmagnetotail

N.A.Case(1),A.Grocott(1),andS.Haaland(2)

(1)LancasterUniversity,(2)UniversityofBergenWehavecollatedover20yearsofmagneticfield,electricfield,andvelocitydatafromtheGeotail,Cluster,DoubleStar,andThemisspacecraftmissionstoelucidatelarge-scalepatternsintheterrestrialmagnetotail.Wearespecificallyinvestigatingthetime-dependenceoftheconvectiononvariousIMFconditions.Investigationsmayleadtousefulinsightsintomagnetotail-ionsophericcouplingandtheeffectofconvectiononprocessessuchasmagneticreconnectionandsubstormdevelopment.

TheconnectionbetweensmallscalepolarcaparcsandtheLLBL

Maggiolo,R.(1),D.Fontaine(2),K.Hosokawa(3),L.Maes(1),Y.Zhang(4),R.Fear(5),J.Cumnock(6),A.Kozlovsky(7),A.Kullen(8),S.E.Milan(9),andM.Echim(1,10)

(1)BelgianInstituteforSpaceAeronomy,Belgium

(2)LaboratoiredePhysiquedesPlasmas/CNRS,EcolePolytechnique,France(3)UniversityofElectro-Communications,Japan

(4)JHUAppliedPhysicsLaboratory,USA(5)UniversityofSouthampton,UK(6)UniversityofTexasatDallas,USA

(7)SodankylÃGeophysicalObservatory,Finland(8)RoyalInstituteofTechnology,Sweden(9)UniversityofLeicester,Leicester,UK.\t

(10)InstituteofSpaceScience,Magurele,Romania

High-latitudeauroralarcsorpolarcaparcs(PCA)consistinthinandelongatedopticalemissionsimilartodiscreteauroralarcsbutlocatedinthepolarionosphere.OnNovember10,2005,high-latitudearcsweredetectedbyanall-skycameraatResoluteBayinCanadaandbytheTIMED/GUVIandDMSP/SUSSIspace-basedimagers.Duringthisperiod,severalPCAsweredetachedfromthedusksideovalandmovedpolewardwhilepointinginthecuspdirection.Onthesameday,theClusterspacecraftwereflyinginthedawn-duskdirectionfromtheloberegionataltitudesaround5REtothedusksidemagnetopause.Clusterobservationsrevealthe

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presenceoffield-alignedaccelerationregionsabovethepolarionosphereassociatedwiththehigh-latitudearcsdetectedbytheimagers.WeanalyzeClusterparticleobservationsfromtheloberegiontothedusksidemagnetopause.AbovePCAs,Clusterdetectsupgoingionsandprecipitatingelectronsacceleratedbyaquasi-staticelectricfield.Theseacceleratedparticlescoexistwithawarmisotropicionpopulationembeddedintheloberegion.Themostequatorwardarcisseparatedfromtheauroralovalbyatransitionregionwhereweakfluxesofionswithplasmasheet-liketemperaturesaredetected.ThentheClusterspacecraftcrosstheplasmasheetuntiltheyreachthelow-latitudeboundarylayer(LLBL)characterizedbyamixtureofplasmasheetandmagnetosheathplasma.ThetransitionregionandtheLLBLaremagneticallyconnected.UsingClusterobservationsweshowthatthesetworegionsdisplaymanysimilarfeatureswhichsuggestthattheoriginofhigh-latitudeauroralarcsmayberelatedtoprocessesoccurringintheLLBLduringperiodsofnorthward.

North-southasymmetriesincoldionoutflowandlobedensity.

S.Haaland(1),L.Maes(2),

K.Laundal(3),B.Lybekk(4),A.Pedersen(4),

(1)Max-PlanckInstitute&BirkelandCentreforSpaceScience,(2)RoyalBelgianInstituteforAeronomy,(3)BirkelandCentreforSpaceScience,

(4)DepartmentofPhysics,UniversityofOslo.Asignificantfractionoftheplasmaintheterrestrialmagnetosphereissuppliedbythehighlatitudeionosphere.Thetransportpathfromtheionospheretothemagnetotailgoesthroughthemagnetotail.Inthispresentation,weshowobservationsindicatingapersistantinterhemisphericasymmetryinionoutflowandloberefilling:Aroundequinox,thecoldplasmadensityinthenorthernhemispherelobeisconsistentlyhigherthanthesouthernlobe.Weinferthatdifferencesinoutflowfromthepolarcapionosphereisthemostlikelyexplanation.Solarwind-magnetosphereinteractionsanddailyandseasonalvariationsintheEarth'sareknowntosetupasymmetriesinionoutflow,butthepersistentasymmetriesreportedhereareprobablyrelatedtonon-dipolartermsintheEarth'sinternalmagneticfieldand/ortime-laggedresponsesinthermosphericproperties.

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Solarzenithangledependency,seasonalvariationsandN-Sasymmetryofthepolarwind

LukasMaes(1),RomainMaggiolo(1),MatsAndré(2),AndersEriksson(3),Stein

Haaland(4,5),KunLi(4)

(1)BelgianInstituteforSpaceAeronomy,Brussels,Belgium,(2)SwedishInstituteofSpacePhysics,Uppsala,Sweden,(4)Max-PlanckInstituteforSolarSystem

Research,Göttingen,Germany,(3)DepartmentofPhysicsandAstronomy,UppsalaUniversity,Uppsala,Sweden,(5)BirkelandCentreforSpaceScience,Universityof

Bergen,NorwayThepolarwindisanimportantprocessthroughwhichionsescapefromtheionosphereandasignificantsourceofplasmaforthemagnetosphericlobesandplasmasheet.Sincesolarilluminationisthemaindriverofthepolarwind,onewouldexpectthatthesolarzenithangleoftheionosphericorigintohaveastrongcontrolontheoutflowingfluxes.DuetotheinclinationofEarth'srotationalaxis,andtheoffsetofthemagneticdipoleaxis,theaveragesolarzenithangleofthepolarionospherevariesonadailyandseasonalbasis.Thereforetheoutflowingionfluxesfromthepolarcapsshouldexhibitsimilarvariations.Moreover,Earth'smagneticfieldisasymmetricbetweenthenorthernandsouthernhemisphere,whichmeansthesouthmagneticpolehasalargeroffsetfromtherotationalaxisthanthenorthmagneticpole.Theionsinthepolarwindaredifficulttomeasureathighaltitudes,however,becausetheytypicallyhavetoolowenergiestoovercomethepotentialcausedbythechargeacquiredbyasatelliteflyingintheseregions.AnalternativemethodusesthetwoelectricfieldexperimentsaboardtheClustersatellitestoestimatetheionfluxesfromthespacecraftpotentialandthewakeformedbehindthechargedspacecraft.AdatasetcompiledbyAndreetal.[2015],usingthismethodandconsistingofmeasurementsover10years,isusedinthisstudytoinvestigatethesolarzenithanglecontroloftheionoutflowfromthepolarcap,aswellasitsseasonalvariationsandpossiblenorth-southasymmetries