Exclusive Neutrino Cross Sections From Mi MiniBooNE Martin Tzanov - PowerPoint PPT Presentation

Exclusive Neutrino Cross Sections From Mi MiniBooNE Martin Tzanov University of Colorado PANIC 2008, 9-14 November, Eilat, ISRAEL

Neutrino no Cross Sec ections Today ay ν ν CC world data CC world data • Precise knowl wledge ge need eded for pr prec ecis ise e oscillat ation on measurements. T2K 2K, BooNE NE • Cross sectio ion we well mea easured ab above 20 20 GeV. K2K, NO NOvA • Few ew meas asurem emen ents be below 20 GeV. MINOS • 20- 0-30 0 years old ld bub ubble chamber ex expe periments (mos ostly H 2 , D 2 ). • Neut utral cur urrent nt cross sections are e even less und nderstood. Martin Tzanov, PANIC 2008

The MiniBooN oNE Experiment ν mode flux - foc ocus usin ing π + BEAM: • Mini niBooNE ex extracts protons from the 8 GeV eV Booster deliver ered d to a 1.7l Be target inserted into o a magn gnetic ic horn (2.5 kV, 174 4 kA) that at (in increa eases es flux ux 6 times) • ~90 900k in interactio ions in n fiducial volume in ν mode with h small an anti- i- ν componen ent. • ~90 90k int nteractio ions in fidu ducial vol olume in an anti- ν mode with h 30% 0% ν component nt. ant nti- ν mode flux - focusing g π - The Neutrino Flux Prediction at Mini niBooNE, Submitted to PRD [arXiv:0806:1449] DETECTOR • 541 41 m downstream am of tar arget et, 3 m overburden • 12 m diameter sphe here( e(10 m “fiducial al”) • 800 00 t (450 t fidu ducia ial) of pu pure e mineral al oil l (CH 2 ) • 128 280 inner and 24 240 vet eto ph photot otube bes The e MiniBooNE Detector, Accepted by NIM A [arXiv:0806.4201] Martin Tzanov, PANIC 2008

ν CCQE µ − ν µ + → µ + n p Neutrino oscil illations: • dominant nt at at this en energy. • golden en channe nel for dis isap appearan ance searches. Neutrino cross section: • prov ovid ides inf nformatio ion about nucle lear structur ure. g = F A ( ) A 2 + 2 2 1 Q M A • fits to ol old bu bubble chamber experiments (D 2 ). - M A = 1.03 GeV. • recent results on nuclear ar target ets – hi higher M A - K2K SciFi ( 16 O) M A = (1. 1.20 ± 0.12) GeV, PRD RD 74, 4, 052 52002 (2006) 6) - K2K Scibar ar ( 12 C) M A = (1.14 14 ± 0.11) 1) GeV eV MiniBooNE NE has coll llected d 198, 8,000 00 events after cuts. Martin Tzanov, PANIC 2008

ν CCQE Kinematics µ • tagged ed by the stoppe ped muon n decay ay elec ectron on • 74% 4% pur urit ity, 35% efficiency • measure e θ µ , T µ → E ν , Q 2 2 = − 2 = − 2 + − θ Q q m 2 E ( E p cos ) µ ν µ µ µ • world M A =1.03 GeV (dashe hed li line) dat ata disagree e in Q 2 • fit to the Q 2 distribu butio ion using ng effective e parameters M A and nd κ (Pauli li bl blocking parameter). M A = (1.23 23 ± 0.20) GeV, (high Q 2 ) Measurement of Muon n Neutrino Quas asi- i- κ = 1.01 019 ± 0.011, (low Q 2 ) Elastic Scat atter erin ing on n Car arbo bon, PRL RL 10 100, 03231 310 (200 008) • agr gree ees wit ith nu nuclear target measurements. Martin Tzanov, PANIC 2008

ν CCQE Kinematics µ Data/MC ratios bef efore correctio ion after correction on = − = − + − θ 2 2 2 Q q m 2 E ( E p cos ) µ ν µ µ µ • improves agree eement with h data for both cos θ µ and T µ Martin Tzanov, PANIC 2008

ν CCQE µ + ν µ + → µ + p n • • ap apply M A and κ from ν mode. e. • goo ood agr gree eement with dat ata. PRELIMINARY PRELIMINARY • goo ood agr gree eement in othe her kinematic var ariables Martin Tzanov, PANIC 2008

ν µ NC π 0 ν + → ν + + π 0 N N resonant µ µ ν + → ν + + π 0 A A coherent µ µ Neutrino oscillation: Neutrino cros oss section: • very import rtant for or ν e appea earance sear arches es • important for or understanding g coheren ent - if if one ne of of the γ ’s is lost or bel elow threshold ld and res esonant produ duction. • no o data bel elow 2GeV eV. Wor orld d data on cohe herent production • Rei ein – Sehg hgal mod odel used for pr predi diction. n. Martin Tzanov, PANIC 2008

ν µ NC π 0 First Observation of Coherent π 0 Production in Neutrino Nucleus Int nteraction ons with E ν <2 GeV, Phys Lett B.664, 41 (2008) • excelle lent π 0 con ontainm nmen ent (4 π ) • very differ erent nt angular ar distrib ibution ons – • fully recon onstructed π 0 sam ampl ple – coh oherent is muc uch more forward 28,600 events, 97% % pur urit ity, 40 40% efficie iency • fit for resona nant and coherent • rewei eighting of mom omen entum distribut ution on fractio ions yield lds [19 19.5±1. 1.1(stat at)±2.5( 5(syst)]% gives ver ery go good agreement nt in in other coh oherent frac action. kinematic variabl bles. Martin Tzanov, PANIC 2008

ν NC π 0 µ ν + → ν + + π 0 N N • • ~27 2700 even ents af after cuts µ µ • evide dence of of cohe heren ent events. • fir irst measurement at at 1GeV For or details see e poster 77 7 by V. Nguyen en comparison w/o coherent nt fraction Martin Tzanov, PANIC 2008

ν µ CC π + − + ν + → µ + + π N N resonant µ − + ν + → µ + + π A A coherent µ ν µ CC π + world data Neu eutrino oscillat ation: n: • major or background nd for ν µ dis isappear aranc nce - if π + is absorbed ed in n the nuc ucle leus • modif ifies es ν µ QE energy spec ectrum um • results in n larger system emat atic on os oscill llation on parameters. • nee eed to kno now ν µ CC π +/ ν µ CCQE(E ν ) to o better than 5%. Neu eutrino cross section: • old ld bub ubble e chamber da data a (H 2 , D 2 ). • few nuclear target exper erim imen ents. Also talk by SciB iBooNE – Y. Nak akaj ajima • evid idence of no cohe heren ent com ompo ponent at low ener ergy gy. Martin Tzanov, PANIC 2008

ν µ CC π +/ ν µ CCQE(E ν ) • tagged d by two stopped d muon • MiniB iBooNE measurement nt is is consisten ent decay el electrons – 47,000 events with previou ous measurements and d 87% % purity, 12% % ef effic icienc ncy Rein- n-Sehg hgal mod odel. • measure θ µ , T µ → E ν , Q 2 • For det etails see pos oster 79 9 by J. Nowa wak. Martin Tzanov, PANIC 2008

ν CC π + - Fully Reconstruc ucted µ • reconstructing both h µ and nd π • most pions undergo go nuclea ear inter eractions resul ultin ing in in kinked tracks. PRELIMINARY • new ew fit itter er look oks for 1 straight ht (muon on) and nd one ne kinked (pion) track. Effectivel ely it’s a three e ring fitter. • fir irst delt lta peak from neu eutrino experiment in more than 20 yea ears. Martin Tzanov, PANIC 2008

Mor ore Cross Sections - ν µ CC π 0 and ν µ NC elastic ν µ NC elas astic different ntial l cros oss section ν µ CC CC π 0 differ eren ential al cross section on − ν µ + → µ + + π 0 n p • preli liminary result using g prompt ligh ght for pr proton n PID. • tagged ed by one stopped ed muon • new ew proton track fit itter will provide decay el electron. proton n PID D and d better recon onstruction on. • onl nly resonant compone nent. • new ew three ring ng fit itter er – muon on and 2 ga gamma a tracks • full ev event reconstruction on. Martin Tzanov, PANIC 2008

Published ed and Future Cross Section Papers MiniBooNE NE cross section and d other relev evant nt papers: • Measurement of Muon Neutrino Quasi-Elastic Scattering on on Carbon on, PRL 100 00, 032 3231 310 0 (2008) • First Observation of Coherent π 0 Production in Neutrino Nucleu eus Interactions with E n <2 GeV, Phys Lett B.664, 41 (2008) • The Neutrino Flux Predi diction at MiniBooNE, Submitted to PRD [arXiv:0806:1449] • The MiniBooNE Detector, Accepted by NIM A [arXiv:0806.4201] Papers in in the he immedia iate e future: • ν µ CC CCp+/ ν µ CCQE(E n ) ratio io measurement nt (S. Linde den, J. Nowak) • NC π 0 coh oherent/resonant nt fraction for anti- i-ne neutrin ino (V. Nguyen n ) Papers to follow w - Dif iffer erentia ial cross section ons: • ν µ CC CCQE, (T. Katori), an anti- ν µ CCQE (T. Laird, d, J. Grange ge) • ν µ CC CC π + (M. Wilk lking) • ν µ NC NC π 0 (C. Ande derson) • NC elas astic (D. Perevalov) • ν µ CC CC π 0 (R. Nelson) Martin Tzanov, PANIC 2008

BACKUPS Martin Tzanov, PANIC 2008

MiniBoo ooNE Collaboration University of Alabama Los Alamos National Laborator ory Bucknell University Louisiana State University University of Cincinnati University of Michigan University of Color orad ado Princeton University Columbia University Saint Mary’s University of of Minnesota Embry Riddle University Virginia Polytechnic Institute Fermi National Accelerator Laboratory Wester ern n Illinois University Ind ndiana Univer ersity Yale University Martin Tzanov, PANIC 2008