Cosmic Rays in the Heliosphere ECRS2006 - XX European Cosmic Ray Symposium Mikhail Panasyuk Moscow State University

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<ul><li> Slide 1 </li> <li> Cosmic Rays in the Heliosphere ECRS2006 - XX European Cosmic Ray Symposium Mikhail Panasyuk Moscow State University </li> <li> Slide 2 </li> <li> Cosmic Rays in the Heliosphere Galactic Cosmic Rays Anomalous Cosmic Rays Solar Cosmic Rays We imply, that...are the main players... are </li> <li> Slide 3 </li> <li> Energy spectra of cosmic rays (solar minimum) Galactic cosmic rays (H) lg E (eV/nucl) 3912 10 -10 0 lg I 1 MeVn 6 1 GeVn 1 TeVn 1keV/n NOT SCALED Anomalous cosmic rays (O) </li> <li> Slide 4 </li> <li> Energy spectra of cosmic rays (solar maximum) Galactic cosmic rays (H) lg E (eV/nucl) 3912 10 -10 0 lg I 1 MeVn 6 1 GeVn 1 TeVn 1keV/n NOT SCALED Anomalous cosmic rays (O) </li> <li> Slide 5 </li> <li> Energy spectra of cosmic rays (solar maximum) Solar wind (H) Solar energetic particles (H) Galactic cosmic rays (H) lg E (eV/nucl) 3912 10 -10 0 lg I 1 MeVn 6 1 GeVn 1 TeVn 1keV/n NOT SCALED Just a tendency! </li> <li> Slide 6 </li> <li> The basic problems of cosmic radiation study : Sources: - Where do the particles come from ? Particles transport : - How do they propogate through heliosphere medium ? and acceleration processes - How and where they get accelerated? </li> <li> Slide 7 </li> <li> Galactic &amp; Anomalous Cosmic Rays </li> <li> Slide 8 </li> <li> GCR chemical composition/spectra * Galactic and extra- Galactic origin. Practically all elements. Fully ionized * Omnidirectional 10 8 - 10 21 eV. * Solar cycle modulation (11 years) at low energies. </li> <li> Slide 9 </li> <li> Cosmic ray composition GCR: 90% H, 9% He, 1% CNO Enrichment by secondaries: Li,Be,B ACR: He, N, O, Ne, but few C, Mg, Si, Fe; O/C 5 ( whereas in GCR O/C~1). Li,Be,B </li> <li> Slide 10 </li> <li> Propagation and temporal variations Modulation of GCR (neutron monitors data) Solar activity - Scattering on magnetic irregularities - diffusion; - A diffusion coefficient is the product of particle speed with an increasing function of rigidity. Equatorial region Polar region </li> <li> Slide 11 </li> <li> Propagation and temporal variations Modulation of ACR </li> <li> Slide 12 </li> <li> Modulation of GCR &amp; ACR Weak modulation for GCR Strong modulation for ACR Charge-Sign Dependent Solar Modulation Charge-Sign Dependent Solar Modulation C 5+ -6+ O+ </li> <li> Slide 13 </li> <li> Where is modulation region? The radial GCR intensity distributions indicates the changes at ~15-25 AE with much stronger modulation for solar max at outer heliosphere, it means that 11-year modulation are mainly occuring in the outer heliosphere between 15 AE and TS (McDonald, et al, 2003) </li> <li> Slide 14 </li> <li> Modulation of ACR Results of analysis of ACR oxygen at Cosmos,WIND, Pioneer 10, Voyager 1 and Voyager 2 during 1972- 1999 give an estimation of modulation boundary - Bm ) location near ~90AE. ( Zhuravlev, et al, 2004). Modulation boundary R,AE Intensity Min SA,A&gt;0 Max SA ~90AE </li> <li> Slide 15 </li> <li> Leaky-box model and modulation esc E,MeV 10 3 10 2 10 4 Soutoul- Ptuskin strongmodel : esc ~ 3 R 2 including effects of galactic wind Higher energies escape easily from Galaxy Effects of distributed CR acceleration as they pass through the interstellar medium </li> <li> Slide 16 </li> <li> Leaky-box model and modulation Soutoul- Ptuskin strongmodel : esc ~ 3 R 2 including effects of galactic wind There is an agreement with: CRIS/ACE data Davis, et al, 2000 But.. </li> <li> Slide 17 </li> <li> Leaky-box model and modulation But theordinary esc (E) dependence at low energy with a LOCAL SOURCE of CR give the close results, exept Sc-Ti- V group. Therefore we cannot exclude the existence of local source </li> <li> Slide 18 </li> <li> Charge state of cosmic rays 1 10100 8+ 1+ Q SW GCR (oxygen) SEP Direct methods Geomagnetic cutoff 0.1 MeV/nucl ACR </li> <li> Slide 19 </li> <li> Partially ionized HZE ions in the cosmic rays Salyut - 6 data a region where a completely stripped Fe nuclei would be forbidden. Expected cutoff Latitude The most possible explanation of these observations that there are partially ionized iron ions at energy of ~ 200 Mev/nucl. </li> <li> Slide 20 </li> <li> Partially ionized HZE ions in the cosmic rays Experiment The last publication Astro (Salut 6,1981) (Blazh et al, 1986) Anuradha ( Spacelab 3) (Dutta et al, 1993) Kashtan (Cosmos, 1990) (Grigorov, et al 1991) LDEF (1984 1989) (Tylka, et al, 1995) </li> <li> Slide 21 </li> <li> About sources How to explain low charge state of low -energy GCR? - Local sources? - A possible way... Red Dwarfs (after Yu. Stozhkov)? Charge state of ACR (He, O...)- 1+ Are there a sources of ACR nearby? For Red Drafts it should be proposed an existence of abnormal chemical composition </li> <li> Slide 22 </li> <li> The main statements of the Fisk, Kozlovski Ramaty theory The anomalous cosmic ray component Penetration of ISM neutrals from the interstellar medium into the heliosphere; </li> <li> Slide 23 </li> <li> The main statements of the Fisk, Kozlovski Ramaty theory The anomalous cosmic ray component Then Ionization of neutrals due to ultraviolet and charge-exchange with ions of the solar wind; </li> <li> Slide 24 </li> <li> The main statements of the Fisk, Kozlovski Ramaty theory The anomalous cosmic ray component Then Acceleration of ionized neutrals, picked-up by the solar wind from ~4 keV/nucleon to &gt;10 MeV/nucleon at the heliopause (termination shock); </li> <li> Slide 25 </li> <li> The main statements of the Fisk, Kozlovski Ramaty theory The anomalous cosmic ray component And then they will undergo modulation and propagation inside the heliosphere </li> <li> Slide 26 </li> <li> The anomalous cosmic ray source Adams, J.H. and Leising, M.D., 1991.: Losses by charge exchange reactions of O (O + -&gt;O n+ ) n H = 0,1 /cm 3, =1+, ACR life- time limit and source region: d max ~ 0,2 pc, or d max /v = 4,6 years - Local ISM dust is source of ACR </li> <li> Slide 27 </li> <li> ACR source(s) Alternative (or complementary) approach: Ionosphere plasma of magnetic planets enriched by O+ can be a source for ACR </li> <li> Slide 28 </li> <li> Ionosphere as a source of plasma in the Earths magnetotail +,He+,O+ </li> <li> Slide 29 </li> <li> Magnetic substorms/storms reconnection Particles acceleration and outflow in antisolar direction </li> <li> Slide 30 </li> <li> Magnetic substorms/storms reconnection Particles acceleration and outflow in antisolar direction </li> <li> Slide 31 </li> <li> Magnetic substorms/storms reconnection Particles acceleration and outflow in antisolar direction Magnetic reconnection </li> <li> Slide 32 </li> <li> Thermal plasma in the planetary ionospheres JupiterSaturnUranusNeptune SourcesIo, moon Ionosphere I cy moons, SW Ionosphere Triton, moon Composition H,Na,O,K,S,H 2 O,N H,OH,H 2, O,N H,HeN,H,He Source strength ~3x10 28 i/sec 10 26 i/sec10 25 i/sec3x10 25 i/sec Large amount of H, ions heavier than He, and ~ absence of 12 C </li> <li> Slide 33 </li> <li> Estimation of internal ion source strength How strong should be an internal (heliospheric) source of ions to fill the heliospheres volume during a time less than (say) half of solar cycle? </li> <li> Slide 34 </li> <li> Estimation of internal ion source strength Then reqiured strength for internal ion source: S = n esc V H / T ~ 4x10 19 c -1 which is much less than known Jupiters ionosphere source strength S J ~ 10 28 c -1 Need to be involve in calculation: acceleraton efficiency and escaping of particles from magnetospheric tails of the planet into heliosphere </li> <li> Slide 35 </li> <li> Internal ACR source Galactic Cosmic rays Jupiters magnetosphere, 0,1 A.U. O+ Double acceleration of ACR: during reconnection process in the magnetospheres of the giant planets plus acceleration at heliospheric TS </li> <li> Slide 36 </li> <li> Consequences of the Model of internal source 1.Jovian ionosphere is a strongest strength source: S J ~ 10 28 ions/sec; plus Earth, Saturn, Uranus and Neptune ionosphere sources. They can supply O+( and some other ions) into heliosphere. 2. No composition problem: absence of 12 C in a source. But where is S? 3. Ions can be preaccelerated in the giant planets magnetospheres sulfur ? </li> <li> Slide 37 </li> <li> Reconnection is everywhere In the magnetospheres At the Sun </li> <li> Slide 38 </li> <li> Magnetic reconnection as a main force for solar flare particle acceleration Solar flare standard model </li> <li> Slide 39 </li> <li> Particle Acceleration in Flares Acceleration by DC electric field in Reconnecting Current Layer plus... Collapsing trap dynamics Stochastic dynamics (waves, shocks) </li> <li> Slide 40 </li> <li> 1.Magnetic reconnection as an injector Scenario of acceleration process Reconnection region Chromosphere Flares loops - Magnetic field lines move to the X-type neutral point -The electric field is induced and accelerates particles After Somov &amp; Bogachev </li> <li> Slide 41 </li> <li> 1.Magnetic reconnection as an injector Betatron acceleration connected with collaps of magnetic loops with simultaneous Fermi acceleration (stochastic acceleraton) Scenario of acceleration process 2.Electron capture and collaps of magnetic trapping region Reconnection region Chromosphere Flares loops </li> <li> Slide 42 </li> <li> The betatron effect significantly increases the efficiency of the first-order Fermi-type acceleration Collapsing traps with a residual length (without shock) accelerate protons and ions well Somov, B.V. and Bogachev, S.A., Astronomy Letters, 29, 621, 2003 Scenario of acceleration process </li> <li> Slide 43 </li> <li> Stochastic acceleration throughout the loop - Miller/Petrosian Turbulent acceleration site Reconnection acceleration site </li> <li> Slide 44 </li> <li> Solar flare standard model Theoreticians state that SM can explain: energy release; particle acceleration mechanism; flares loops formation; and HXE emission sources. </li> <li> Slide 45 </li> <li> SEP acceleration mechanism should explain experimental data : Acceleration of Electrons up to 0.5s 60-100MeV Protons up to 1-10s 300MeV-GeV SM gives </li> <li> Slide 46 </li> <li> Acceleration of protons and electrons Protons Electrons Bogachev, et al Protons can be accelerated up to GeV, but electrons only up to several MeV Dependent on the plasma parameters Plasma temperature, keV Escaping energy, MeV </li> <li> Slide 47 </li> <li> An additional diagnostic tools for solar flare dynamics and SEP acceleration mechanisms </li> <li> Slide 48 </li> <li> Gamma-ray and neutron production in solar flares Electrons: x- ray, gamma-ray bremstruhlung Ions: exited nuclei lines 1-8 MeV nuclear reactions: neutrons free escaping 2,22 MeV gamma (H-capture) 0 -decay - emissions E &gt; 10 MeV Corona Chromosphere </li> <li> Slide 49 </li> <li> Simultaneous measurements of protons, electrons, rays and neutrons can provide an important information about the nature of generation mechanism of SEP during solar flare An example: Coronas F data during October,28 SEE event </li> <li> Slide 50 </li> <li> CORONAS-F data during Oct., 28, 2003 event The first phase The second - delayed phase Pion-decay production Protons, neutrons, electrons, and gamma - rays </li> <li> Slide 51 </li> <li> spectra during solar flares -ray spectra during solar flares Appearance of a bump in -spectrum as evidence for 2-stages acceleration process during solar flare: the most energetic particles are generated during the 2-nd, delayed phase There is real evidence for solar electron fluxes generation up to energy 60 MeV with via the decay process. </li> <li> Slide 52 </li> <li> Generaton of electrons via -decay e decay process Kuznetsov et al, 2006 Coronas F data Electron spectrum </li> <li> Slide 53 </li> <li> Acceleration of SEP during propagation Fermi acceleraion Berezhko :ions up GeV ! </li> <li> Slide 54 </li> <li> N.Gopalswami: If these SEPs are accelerated by CME- driven shocks, they use a significant fraction of the shock kinetic energy (~3% to 20%) CME shock acceleration </li> <li> Slide 55 </li> <li> SEP acceleration mechanisms Parallel to B Field A: Electric Fields: Parallel to B Field B: Fermi Acceleration First Order Fermi 1. Shocks: First Order Fermi Second Order Fermi 2. Stochastic Acceleration: Second Order Fermi </li> <li> Slide 56 </li> <li> Shocks acceleration is everywhere! SW GCR N ~ 1cm -3 10 -3 cm-3 B ~ 1nT 10 -2 nT T ion ~ 10 eV 10 3 eV Mach ~ 5 100 T ~ hours minutes CME SN </li> <li> Slide 57 </li> <li> The main statements of the Fisk, Kozlovski Ramaty theory The anomalous cosmic ray component Then Acceleration of ionized neutrals, picked-up by the solar wind from ~4 keV/nucleon to &gt;10 MeV/nucleon at the heliopause (termination shock); </li> <li> Slide 58 </li> <li> The anomalous cosmic ray acceleration FIRST ORDER FERMI OR COMPRESSIVE SHOCK ACCELERATION Krymski (1977), Axford et al. (1977) and Blandford and Ostriker (1978): </li> <li> Slide 59 </li> <li> The anomalous cosmic ray acceleration 1st order FermiShock drift +irregularities Acceleration efficiency increases toward the more perpendicular the geometry of shock and s compression factor Electric field E= -V/B </li> <li> Slide 60 </li> <li> The anomalous cosmic ray acceleration 1st order FermiShock drift +irregularities Acceleration efficiency increases toward the more perpendicular the geometry of shock and s compression factor Electric field E= -V/B But: there is pre-acceleration/injection problem which remains one of the main research problems. Basically, for typical parameters the pick up ions must be accelerated by a factor of 100 before the perpendicular shock becomes efficient </li> <li> Slide 61 </li> <li> Internal ACR source Galactic Cosmic rays Jupiters magnetosphere, 0,1 a.e O+ Internal ACR model : Acceleration of ACR during reconnection process in the magnetospheres can provide preacceleration process </li> <li> Slide 62 </li> <li> Consequences of the Model of internal source Ions can be preaccelerated in the giant planets magnetospheres No injection problem </li> <li> Slide 63 </li> <li> Direct observation of ACR acceleration: Voyager data </li> <li> Slide 64 </li> <li> ACR spectra near an outer acceleration region Expected ( from Fermi acceleration ) ACR before TS and inside the heliosphere 10 MeV/ nucleon E j Modulation </li> <li> Slide 65 </li> <li> ACR He Spectral Evolution V1 crossed shock on 2004/351 between bottom two spectra on left Expected source spectrum was not observed at time of shock crossing V1 ACR He spectrum is unrolling in heliosheath as though V1 is closer to the source than V2, but note: V1 now ~10 AU downstream V2 now </li></ul>