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Neutrino Physics - Lecture 7. Steve Elliott LANL Staff Member UNM Adjunct Professor 505-665-0068, [email protected]. Lecture 7 Outline. Accelerator Neutrinos - short - medium baseline The neutrinos Past experiments What we know and what we want to learn Most slides from Bill Louis. - PowerPoint PPT Presentation
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Neutrino Physics - Lecture 7Steve ElliottLANL Staff MemberUNM Adjunct Professor505-665-0068, [email protected]
Steve Elliott, UNM seminar series
Lecture 7 OutlineAccelerator Neutrinos - short - medium baselineThe neutrinosPast experimentsWhat we know and what we want to learn
Most slides from Bill Louis
Steve Elliott, UNM seminar series
The LSND Puzzle and MiniBOONE
Steve Elliott, UNM seminar series
The Evidence for Neutrino Oscillations
Steve Elliott, UNM seminar series
Requires a 3rd m2
Steve Elliott, UNM seminar series
Current State of Neutrino Oscillation EvidenceExpt.TypeDm2 (eV2) sin22q
LSNDnm->ne ~1 ~3x10-3
Atm. nm->nx~2x10-3~1
Solarne->nx ~8x10-5~0.8
Steve Elliott, UNM seminar series
MiniBooNE Neutrino Oscillation UpdateNeutrino Oscillations & the 3 m2 Problem!?! (Sterile Neutrinos?)MiniBooNE: A Definitive Test of the LSND Neutrino Oscillation SignalFuture Neutrino Experiments: BooNE & OscSNS
Steve Elliott, UNM seminar series
If MiniBooNE Confirms LSND: Physics Beyond the Standard Model & Connections with Astrophysics!3+2 Sterile Neutrinos Sorel, Conrad, & Shaevitz (PRD70(2004)073004)Explain Pulsar Kicks?Explain R-Process in Supernovae?Explain Dark Matter?
MaVaNs & 3+1Hung (hep-ph/0010126)Sterile NeutrinoKaplan, Nelson, & Weiner (PRL93(2004)091801) Explain Dark Energy?CPT Violation & 3+1 Barger, Marfatia, & Whisnant (PLB576(2003)303)Sterile NeutrinoExplain Baryon Asymmetry in the Universe?Quantum DecoherenceBarenboim & Mavromatos (PRD70(2004)093015)Lorentz ViolationKostelecky & Mewes (PRD70(2004)076002)Katori, Kostelecky, Tayloe (hep-ph/0606154)Extra DimensionsPas, Pakvasa, & Weiler (PRD72(2005)095017)Sterile Neutrino DecayPalomares-Ruiz, Pascoli, & Schwetz (JHEP509(2005)48)
Steve Elliott, UNM seminar series
Probability of Neutrino OscillationsPab = dab - 4SiSj |Uai U*bi U*aj Ubj | sin2(1.27Dmij2L/En) As N increases, the formalism gets rapidly more complicated!N#Dmij2#qij#CP Phases
2 1 10/1
3 2 31/3
6 515 10/15
Steve Elliott, UNM seminar series
MiniBooNE: A Definitive Test of the LSND Evidence for Oscillations: Search for nm -> neAlabama, Bucknell, Cincinnati, Colorado, Columbia, Embry-Riddle, Fermilab, Indiana, Los Alamos, LSU, Michigan, Princeton, St. Mary's, Western Illinois, YaleCompletely differentsystematic errors than LSND
Much higher energythan LSND
Blind Analysis
Steve Elliott, UNM seminar series
Steve Elliott, UNM seminar series
MiniBooNE HighlightsMiniBooNE began taking data in September 2002 and has collected ~750K neutrino events from ~7E20 Protons on Target; Oscillation analysis will use ~600K events from ~5.7E20 POTExperiment is working well (99% livetime & 99% of PMT channels working well) Clearly reconstructing CCQE, CCPI+, NCPI0, & NCEL eventsFirst focussing horn was replaced during 2004 fall shutdown after setting a world record of 96M pulses (previous record set at BNL with 13M pulses); Second horn now has >100M pulsesNow taking data with Antineutrinos (since January 2006)
Steve Elliott, UNM seminar series
MiniBooNE Neutrino FluxHARP at CERNE910 at BNL
Steve Elliott, UNM seminar series
Expected MiniBooNE Events
Steve Elliott, UNM seminar series
After ne PIDSelection(from proposal)
Steve Elliott, UNM seminar series
Expected MiniBooNE Sensitivity(from proposal)(from proposal)
Steve Elliott, UNM seminar series
Measurement of Oscillation Parameters(from proposal)
Steve Elliott, UNM seminar series
Likelihoods for Contained NuMI 1 Sub-Events Good agreement between data and MC!Preliminary!
Steve Elliott, UNM seminar series
BackgroundsNon- ne BackgroundsBeam OffCC InclusiveNC p0NC D->NgNC Coherent gNC Radiative gIntrinsic- ne BackgroundsFrom m -> ne decayFrom K-> ne decayFrom p -> ne decay
Steve Elliott, UNM seminar series
Beam-Off Background is Negligible! Neutrino Signal to Cosmic-Ray Background ~ 5000 to 1!
Steve Elliott, UNM seminar series
Good PID Agreement for CC Inclusive Events PIDCC inclusive events tagged by Michel electrons
92% of m- decay8% of m- capture
MC is correctlyestimating CCinclusive background
Preliminary!
Steve Elliott, UNM seminar series
MiniBooNE NC p0 Events are MeasuredDMp ~ 20 MeV
Steve Elliott, UNM seminar series
Gamma BackgroundsNC D->Ng : BR ~ 0.56% at peak; small but non-negligible background; now properly handled by modified version of NUANCENC Coherent g : Calculated from Rein & Sehgal (Phys. Lett. 104B (1981) 394) & estimated to be negligibleNC Radiative g : Two sources have been considered, and both are negligible: (1) Bremsstrahlung Term, where g emanates from recoil proton; (2) Contact Term, where g emanates from the interaction vertex
Steve Elliott, UNM seminar series
Intrinsic ne BackgroundsFrom m -> ne decay : Well determined from nm CCQE eventsFrom K-> ne decay : Measure kaon-induced neutrino flux at high energies & extrapolate to low energiesFrom p -> ne decay : Well determined from nm CCQE events
Steve Elliott, UNM seminar series
Expectations for 5E20 Protons on TargetPreliminary!
Steve Elliott, UNM seminar series
MiniBooNE ScheduleContinue Antineutrino RunComplete Neutrino Oscillation Analysis (Estimate systematic errors from neutrino flux, cross sections, detector MC)Open Box and Present ResultsIf MiniBooNE Confirms LSND => Physics Beyond the Standard Model!
Steve Elliott, UNM seminar series
Future Experiments: BooNE & OscSNSWhat new physics is there Beyond the Standard Model?BooNE would involve a second MiniBooNE-like detector (~$8M) at FNAL at a different distance; with 2 detectors, many of the systematics would cancelOscSNS would involve building a MiniBooNE-like detector (~$12M) with higher PMT coverage at a distance of ~60 m from the SNS beam stop at ORNL
Steve Elliott, UNM seminar series
BooNE at FNALTwo identical detectors at different distances
Search for sterileneutrinos via NCPI0scattering & NCEL scattering
Problem: imprecise n energy determinationsmears oscillations!
Steve Elliott, UNM seminar series
OscSNS at ORNLnm -> ne D(L/E) ~ 3% ; ne p -> e+ nnm -> ns D(L/E) < 1% ; Monoenergetic nm !; nm C -> nm C*(15.11)OscSNS would be capable of making precision measurements of ne appearance & nm disappearance and proving, for example, the existence of sterile neutrinos! (see Phys. Rev. D72, 092001 (2005)). Flux shapes are known perfectly and cross sections are known very well.SNS: ~1 GeV, ~1.4 MW
Steve Elliott, UNM seminar series
Search for Sterile Neutrinos with OscSNS Via Measurement of NC Reaction: nm C -> nm C*(15.11)Garvey et al., Phys. Rev. D72 (2005) 092001
Steve Elliott, UNM seminar series
KARMEN Measurement of nm C -> nm C*(15.11)sNC = (3.2+-0.5+-0.4)x10-42 cm2 (B. Armbruster et al., Phys. Lett. B423 (1998) 15)
sNC ~2.8x10-42 cm2 (Kolbe, Langanke, & Vogel, Nucl. Phys. A652 (1999) 91)
Steve Elliott, UNM seminar series
Measurement of 3+2 Model with OscSNS (Sorel et al., Phys. Rev. D70 (2004) 073004)
Steve Elliott, UNM seminar series
ConclusionsMiniBooNE will soon test the LSND Oscillation SignalIf the LSND Signal is Confirmed, then Future Oscillation Experiments Would Provide a Great Opportunity for Neutrino Physics: BooNE at FNAL & OscSNS at ORNLMake Precision Measurements of Oscillation ParametersResolve 3 m2 Paradox & Explore Physics Beyond the Standard Model! (e.g. Sterile Neutrinos)
Steve Elliott, UNM seminar series