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P AUL N IENABER S AINT M ARY ’ S U NIVERSITY OF M INNESOTA FOR THE M INI B OO NE C OLLABORATION J ULY 28 2009 -- DPF2009
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motivated by LSND observation of electron antineutrino events in a muon antineutrino beam 28 July 2009MiniBooNE Update -- DPF20092 PRD 64, 112007 (2001)
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motivated by LSND observation of electron antineutrino events in a muon antineutrino beam MB start: muon neutrino beam different L, E; same L/E 28 July 2009MiniBooNE Update -- DPF20093
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motivated by LSND observation of electron antineutrino events in a muon antineutrino beam MB start: muon neutrino beam different L, E; same L/E 6.9 E+20 POT neutrino mode 5.1 E+20 POT antineutrino mode 28 July 2009MiniBooNE Update -- DPF20094 about 2 mg of protons delivered to date!
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motivated by LSND observation of electron antineutrino events in a muon antineutrino beam MB start: muon neutrino beam different L, E; same L/E 6.9 E+20 POT neutrino mode 5.1 E+20 POT antineutrino mode 28 July 2009MiniBooNE Update -- DPF20095 pion production (& hence flux) well constrained by HARP data/analysis Eur. Phys. J. C52, 29 (2007)
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28 July 2009MiniBooNE Update -- DPF20096 Collaborators from Alabama, Bucknell, Cincinnati, Colorado, Columbia, Embry- Riddle, Fermilab, Florida, Illinois, Indiana, Los Alamos, LSU, MIT, Michigan, Princeton, Saint Mary’s, Virginia Tech, Yale
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cross section measurements oscillation analyses 28 July 2009MiniBooNE Update -- DPF20097
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28 July 2009MiniBooNE Update -- DPF2009 8 neutrino CC cross sections when dinosaurs roamed the Earth (i.e., pre- MiniBooNE)
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these numbers are of fundamental interest, but also relevant to future experiments 28 July 2009MiniBooNE Update -- DPF2009 9
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these numbers are of fundamental interest, but also relevant to future experiments 28 July 2009MiniBooNE Update -- DPF2009 10 NOvA T2K CNGS DUSEL
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these numbers are of fundamental interest, but also relevant to future experiments focus here on two processes: CC QE (signal for oscillation) 28 July 2009MiniBooNE Update -- DPF2009 11
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these numbers are of fundamental interest, but also relevant to future experiments focus here on two processes: CC QE (signal for oscillation) NC π 0 (background) 28 July 2009MiniBooNE Update -- DPF2009 12
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LARGE SAMPLE! 146,070 QE events (76% purity, 27% ) [analyzed, after cuts] provide most complete information on QE scattering to date (full kinematics: E and ) 28 July 2009MiniBooNE Update -- DPF2009 13 W+W+ n
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(T. Katori) 28 July 2009MiniBooNE Update -- DPF2009 14 W+W+ n T (GeV) cos (draft in preparation)
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(T. Katori) 28 July 2009MiniBooNE Update -- DPF2009 15 W+W+ n T (GeV) cos first double differential cross section for QE!! (draft in preparation)
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28 July 2009MiniBooNE Update -- DPF2009 16 W+W+ n - Q 2 shape fit results: M A =1.35 0.17 GeV - Higher value of M A also consistent with total vs. E - Consistent w/ K2K, MINOS, but not w/ M A D 2 =1.03 GeV
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28 July 2009MiniBooNE Update -- DPF2009 17 W+W+ n - Q 2 shape fit results: M A =1.35 0.17 GeV - Higher value of M A also consistent with total vs. E - Consistent w/ K2K, MINOS, but not w/ M A D 2 =1.03 GeV preliminary RFG = relativistic Fermi gas (v. Smith & Moniz, NP B43, 605 [1972]) model predictions, NOT fits
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28 July 2009MiniBooNE Update -- DPF2009 18 W+W+ n preliminary MiniBooNE and recent SciBooNE in good agreement Both higher than recent NOMAD QE ?! (all three on 12 C) look to MINOS and MINER A for more data MINOS, MINER A
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28 July 2009MiniBooNE Update -- DPF2009 19 n,p 00 0 LARGE SAMPLE! neutrino: 21,542 NC 0 events (73% purity, 36% ) antineutrino: 2,305 NC 0 events (58% purity, 36% )
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28 July 2009MiniBooNE Update -- DPF2009 20 n,p 00 p (GeV) cos cos (C. Anderson) [flux averaged] (draft in preparation)
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28 July 2009MiniBooNE Update -- DPF2009 21 n,p 00 p (GeV) cos cos (C. Anderson) first measurement of absolute NC 0 differential cross section [flux averaged] (draft in preparation)
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28 July 2009MiniBooNE Update -- DPF2009 22 M O R E ! ! ! -- CC + /CCQE: arXiv:0904.3959 [hep-ex] [S Linden, J Nowak] -- CC + : d /dT , d /d d 2 /dT d d /dT , d /d , d 2 /dT d ,d /dQ 2, (E ) [M Wilking] -- NC elastic: d /dQ 2 [D Perevalov]
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28 July 2009MiniBooNE Update -- DPF200923 2007 result: In analysis region 475 < E < 3000 MeV, no evidence for oscillation (interpretation of LSND as simple two-neutrino oscillation excluded at 98% CL) Unexpected excess of events at low energy < 475 MeV PRL 98, 231801 (2007) 5.6 10 20 POT
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28 July 2009MiniBooNE Update -- DPF200924 2009 update: improved statistics, better modelling of some background processes, and enhanced cuts on external interactions analysis threshold extended down to 200 MeV over 475 MeV: no change
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28 July 2009MiniBooNE Update -- DPF200925 2009 update: improved statistics, better modelling of some background processes, and enhanced cuts on external interactions analysis threshold extended down to 200 MeV under 475 MeV: excess persists PRL 102, 101802 (2009)
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28 July 2009MiniBooNE Update -- DPF200926 -- statistics are low (does not include spring 2009 runs) -- no definitive statement on LSND yet -- no low energy excess?! __ - arXiv:0904:1958 [hep-ex] - (G. Karagiorgi) arXiv:0904.1958 [hep-ex] submitted to PRL
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28 July 2009MiniBooNE Update -- DPF200927 at 90%CL, no neutrino or antineutrino disappearance observed neutrino results agree with earlier experiments (CDHS + CCFR) antineutrino results map out new excluded region in parameter space arXiv:0903.2465 [hep-ex] (PRL in proof) mode (K. Mahn)
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cross section results: unprecedentedly large samples allow measurements to be unpacked as differential rather than total flux understanding (HARP, &c.) allows absolute rather than ratio measurements some interesting unanswered questions (M A, &c.) oscillations: provenance of low energy excess remains an open question antineutrino results await more statistics 28 July 2009MiniBooNE Update -- DPF200928
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combined antineutrino/neutrino appearance analysis combined MiniBooNE/SciBooNE disappearance analysis three more years antineutrino running 28 July 2009MiniBooNE Update -- DPF200929
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combined antineutrino/neutrino appearance analysis combined MiniBooNE/SciBooNE disappearance analysis three more years antineutrino running MicroBooNE: liquid argon TPC in BNB line, upstream of MiniBooNE upgrade to BooNE: second detector 28 July 2009MiniBooNE Update -- DPF200930 see B Fleming Friday morning plenary!
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