WIXLIB

Toward unified description of lepton-nucleus reactionsfrom MeV to GeV region2014 Feb 9th, KEK Tokai Bldg #1YAMAGATA UNIVERSITYNeutrino nucleon and neutrino nucleuselastic scatteringY. Miyachi, Yamagata University2014/02/9@KEK-TOKAI1

ContentsYAMAGATA UNIVERSITY Neutrino-nucleon or Neutrino-nucleus ? Connection to spin structure of the protonSpin structure of the protonWhatWhat wewe learnedlearned fromfrom DIS.DIS. Role of strange quark spin, Δs Form factors, axial charge and strangenessExperimental results E734, SciBooNE*, MiniBooNE, T2K* Feasibility study done at pre-T2K era ( 2007). Summary in 2007 and now2014/02/9@KEK-TOKAI2

Proton spin problem and ΔsYAMAGATA UNIVERSITYPolarized DIS:⃗ μ ' Xμ N⃗InclusiveInclusivemeasurementmeasurementd σ (x , Q2 )Double spin asymmetryg1A1 F1FromFrom unpol.unpol. DISDISStructureStructure FunctionFunctionF i x ,Q 2 , g i x ,Q 2 mg 1 A1 F 1XP M ,0 12 e q Δ q (x )2 qPartonParton DistributionDistributionq x , Q 2 , q x ,Q 2 12 dx g 1 ( x) 2 e q Δ qq2014/02/9@KEK-TOKAI3

Proton spin problem and ΔsYAMAGATA UNIVERSITY12dxg(x) e 1 qΔq2 q1 2ΔqΔq includesincludes anti-qanti-q Δ q Δ ̄q{( ) ( ) ( ) }232211Δ u Δd 33111 a0 a3 a8912362ΔsProtonProton spinspin budgetbudget1 1 a 0 Δ G L2 2a 0 Δ u Δ d Δ s ?.?a 3 Δ u Δ d 1.26a 8 Δ u Δ d 2 Δ s 0.86 SpolDISβ-decayβ-decayΔuΔdΔs4

CERN-EMC experimentYAMAGATA UNIVERSITY2014/02/9@KEK-TOKAI5

YAMAGATA UNIVERSITY2014/02/9Proton spin problem andNucl.Δs- EMC results Phys. B328 (1989) 1, Phys. Lett. B206 (1988) 364@KEK-TOKAI6

YAMAGATA UNIVERSITYProton spin problem andNucl.Δs- EMC results Phys. B328 (1989) 1, Phys. Lett. B206 (1988) 3641 0 dx gp1(x ) 0.126 0.01 0.015a 0 0.1a 3 1.26a 8 0.582014/02/9@KEK-TOKAI s 0.19NegativelyNegatively polarizedpolarized“strange“strange sea!!”sea!!”7

Polarized DIS experimentYAMAGATA UNIVERSITYBeam26.7 GeV pol. electron/positronBeam160 GeV pol. muonTarget1996-1997Long. HTarget2002 - 2006 Long. Trans. 6LiD.1998-2000Long. D2007Long. Trans. NH32002-2005Trans. H20102006-2007unpol. HTrans. NH32011Long. NH3 JLabJLab experimentsexperiments2014/02/9@KEK-TOKAI8

Updated results on g1 and ΔsYAMAGATA UNIVERSITYNSNS aa33 Δu-ΔdΔu-ΔdNotNot saturatedsaturatedProtonProtonPhys. Rev. D 75 (2007) 012007NotNot saturatedsaturated0.9 0.021 g 1d (x) dx 0.0436 0.0012 0.018 0.0008 0.0026DeuteronDeuteronSaturatedSaturatedΔ s 0.085 0.013 0.008 0.009Δ s 0.08 0.01 0.022014/02/9-- inclusiveinclusive DISDIS-- withsymmetrywith SU(3)SU(3)ff symmetrysymmetrysymmetryPhys. Lett. B 647 (2007) 8※ from global QCD analysisWeitsWe nownow knowknow ΔsΔs withwithits uncertaintyuncertainty δ(Δs)δ(Δs) 0.020.02@KEK-TOKAI9

SU(3)f violation and impact on DsYAMAGATA UNIVERSITYJ.J. LichtenstadtLichtenstadt andand H.H. J.J. Lipkin,Lipkin, Phys.Phys. Lett.Lett. B353B353 (1995)(1995) 119119E.E. LeaderLeader et.et. al.,al.,Phys.Phys. Lett.Lett. B488B488 (2000)(2000) 283283SU(3): symmetric violatedcQMcQM calculation:calculation: (X.(X. SongSong et.et. al,al, Phys.Phys. Rev.Rev. D55D55 (1997)(1997) 2624-2629)2624-2629)SU(3)SU(3) symmetry:symmetry: ΔsΔs -0.1-0.1SU(3)SU(3) breaking:breaking: ΔsΔs -0.05-0.05Possible large contribution from SU(3)f breaking δ(Δs) 0.022014/02/9@KEK-TOKAI10

Flavor tagging in DIS l N l ' h XYAMAGATA UNIVERSITYStructureStructure FunctionFunctionF i x ,Q 2 , g i x , Q 2 FlavorFlavor Tagging:Tagging:PartonParton DistributionDistribution22q (x , Q ), Δ q( x , Q )HadronHadron carriescarries informationinformation ononquarkquark flavorflavorthroughthrough fragmentationfragmentation functionfunctionh2FragmentationFragmentation D q z , Q IdentifyIdentify oneone hadronhadrond 3 Δ σhdx dz dQ2z 2014/02/9p h E h , p h i e Δ q( x , Q ) D ( z ,Q )P ph E h P q2q@KEK-TOKAI2hq211

Δs determination with SIDIS dataYAMAGATA UNIVERSITYPhys. Rev D 71 (2005) 012003 s x 0 assumedΔ s Δ ̄s 0.03 0.03assumingΔq(x) 00.6 q 0.023 dx q x Q 2 2.5 GeV 2 u 0.601 0.039 0.049 d .226 0.039 0.050 u .002 0.036 0.023 d .054 0.033 0.011 s 0.028 0.033 0.0092014/02/9- without SU(3) symmetry assumption- only partial moments are available- “LO” extraction@KEK-TOKAI12

Δs determination with SIDIS dataCOMPASS PRLB693(2010)227YAMAGATA UNIVERSITYΔ s Δ ̄s 0.03 0.03Δ s Δ ̄s 0.02 0.032014/02/9@KEK-TOKAI13

Δs measured in DISYAMAGATA UNIVERSITYInclusive measurement:ΔsΔs -0.08-0.08 0.020.02SU(3)SU(3)ff symmetrysymmetrySemi-inclusive measurement:ΔsΔs 0.030.03 0.030.03FlavorFlavor taggingtaggingWithoutWithout SU(3)SU(3)ffLimitedLimited xx rangerange2014/02/9@KEK-TOKAI14

YAMAGATA UNIVERSITYNucleon Form FactorsAxial charge, and Δs2014/02/9a 0 Δ u Δ d Δ s 0.3a 3 Δ u Δ d 1.26a 8 Δ u Δ d 2 Δ s 0.86 -decayβ-decay15

Nucleon form factorsYAMAGATA UNIVERSITYElectricElectric chargechargeD. H. Beck and B. R. Holstein, J. Mod. Phys. E10 (2001) 1MagneticMagnetic momentmomentSpin: ΔqStrange contribution:s2AG (Q ) 2014/02/9sA2sAG (0) Δ sG (0)2 2A(1 Q / M )@KEK-TOKAI16

Neutrino-Nucleon scatteringYAMAGATA UNIVERSITY2F2Gd Q2 A BW CW 22dQ 2 E 1A G 1 F F 1 4 F F ][421212214 E Q 2W 2m p mpQ2 4m 2p21 G 1 F 1 F 2 421 mp 222G F F 12 16 Q2 1B C NC-EL/CC-QENeutral Current[[[F 1,2 ]11 spn2pn sin 2 W [ F 1,2 F 1,2 sin F F F 1,2]W [ 1,21.2 ]22sGAGAG 1 z 222014/02/9]sA]2G Q 0 s@KEK-TOKAI17

YAMAGATA UNIVERSITYExperimental results onneutral current ν-N(A) cross sectionE734, SciBooNE*, MiniBooNE, T2K*2014/02/9@KEK-TOKAI18

Neutrino scattering and sYAMAGATA UNIVERSITY- E734 results -Neutral current elastic scattering cross sectionLiquid scintillator Drift Tube 170 t0.5E19 POT for neutrino2.5E19 POT for anti-neutrinoE734, Phys. Rev. D35 (1987) 785From GAs(Q2) to ss2G A Q 0 s 0.21 0.10Further analysis based on E734R NC /CC 0.152 0.007 0.017R NC /CC 0.218 0.012 0.023R NC/ 0.302 0.019 0.037-0.21 s 02014/02/9strong correlation with the axial mass MAQ2 dependence of GsA@KEK-TOKAI19

SciBooNEYAMAGATA UNIVERSITY(NuFact06, H. Tanaka)2014/02/9@KEK-TOKAI20

SciBooNEH. Takei, PhD. ThesisYAMAGATA UNIVERSITY2014/02/9@KEK-TOKAI21

PRD82 (2010) 092005MiniBooNEArXiv:1309.7257YAMAGATA UNIVERSITYν N ν NCH2 targetΔ s 0 M A 1.39 0.11 GeVΔ s 0.2 M A 1.35 0.11 GeV2014/02/9@KEK-TOKAI22

Determination of Δs at MiniBooNEPRD82 (2010) 092005YAMAGATA UNIVERSITȲν KAI23

T2K results on neutral current elastic scattering Stat.: 10% (MiniBooNE)YAMAGATA UNIVERSITYStat.: 3%Model for BG process: 15%Flux: 20%Outside BG: 6.4%D. Ruterbories @NuFact 20132014/02/9@KEK-TOKAI24

YAMAGATA UNIVERSITYIs it really possible to extract Δs from R(NC/CC) measurementwith NUCLEAR target?2014/02/9@KEK-TOKAI25

R(NC/CC) and ΔsYAMAGATA UNIVERSITYB. I. S. van der Ventel and J. Piekarewicz,A. Meucci et al.,Phys. Rev. C73 (2006) 025501Nucl. Phys. A 773 (2006) 250Δs -0.1Δs -0.19Δs 0.0Δs 0.0T'p (MeV)a relativistic plane-wavea relativistic imation2014/02/9Both were calculated for 12C.@KEK-TOKAI26

R(NC/CC) and strange form factorsYAMAGATA UNIVERSITYΔs -0.1, μs -0.5(solid) Δs -0.1, μs 0.0(dotted) Δs -0.1, ρs 2Δs 0.0, μs 0.0, ρs 0Strange quark contributionto the magnetic form factor GMsalso contributes to R(NC/CC)2014/02/9@KEK-TOKAI27

YAMAGATA UNIVERSITYGlobal analysis of strange form factorsG2014/02/9sEGsM@KEK-TOKAIGsA28

Strange from factors: GEs and GMsYAMAGATA UNIVERSITYD. H. Beck and B. R. Holstein, J. Mod. Phys. E10 (2001) 1G0, Phys. Rev. Lett. 95 (2005) 092001Parity violating electron-proton scattering2014/02/9@KEK-TOKAI29

Global analysis of the strange form factorsYAMAGATA UNIVERSITY2014/02/9@KEK-TOKAI30

YAMAGATA UNIVERSITYNuclear EffectQ2 dependenceΔsNormalizationStrange formflux/backgroundfactorsAccurate measurement of NC ν-H in 0.1 Q2 0.4 GeV2which is covered by the electron scattering.2014/02/9@KEK-TOKAI31

Methods of s measurementYAMAGATA UNIVERSITYR(NC/CC)R(NC/CC) measurementsmeasurementsNeutrinoNeutrino fluxflux shouldshould bebe canceled.canceled.ItIt alsoalso suppressessuppresses thethe nuclearnuclear effect.effect.IsIs there any model dependence uncertainty?uncertainty?n-Hn-H scatteringscattering extractionextractionUsingUsing twotwo targetstargets withwith differentdifferent mixturemixture ofof HH andand CCSeparationSeparation ofof n-Hn-H andand n-Cn-C scatteringscattering becomesbecomes possiblepossibleNeutrinoNeutrino flux information is neededneeded toto extractextract thethe crosscross section.2014/02/9@KEK-TOKAI32

J-PARC -beam lineYAMAGATA UNIVERSITY※※ FeasibilityFeasibility studystudy donedone forfor T2KT2K inin 20072007Beam flux1 GeV for “on-axis” 1GeV for “off-axis”1021 POT/year (130 days)anti-neutrino beamneutrino anti-neutrinoasymmetry measurementExpected ν flux (MC data)2014/02/9@KEK-TOKAI33

Dual SciBath configurationYAMAGATA UNIVERSITY5m5BC501ABC533WLS readoutm5mFiducial volume:3x3x3 m3Geant4 dataν: 500 MeVp: 270 MeV2014/02/9@KEK-TOKAI34

Extraction of NNCHYAMAGATA UNIVERSITYNuclear effect free extraction:Using two liquid scintillators with different mixture of H and C:BICRON: H/Cρ(g/cm3)ρH(g/cm3) ρC(g/cm3)BC501A1.2120.8740.1120.688BC533 1.960.80.0800.794HNCCNCBC533NCBC533NCN 23.4 NN 2.36 N2014/02/9BC501ANCBC501ANC 20.3 N 3.30 N@KEK-TOKAI( 15% *NNC )35

Expected sensitivityYAMAGATA UNIVERSITYStat. Sys. errorsStatistical error onlyδ(Δs) 0.03(dipole form factor)Expected sensitivity assuming the dipole approximation:δ(Δs) 0.03Systematic errors must be studied carefully. (Normalization, Background)2014/02/9@KEK-TOKAI36

Summarygivengiven atat workshopsworkshops inin 20072007YAMAGATA UNIVERSITYProton spin problemΔs is a key for understanding of sea quark contributionHERMES, COMPASS: Δs -0.08 0.02 with SU(3) symmetryHERMES SIDIS: Δs 0.03 0.03 ( partial, no SU(3) symmetry)Strange nucleon form factor constrains Δs first momentNeutrino scattering: NC elastic scatteringE734 NC cross section measurements : -0.2 Δs 0.0FINeSSE proposed R(NC/CC) measurement : δ(Δs) 0.04SciBooNE: Data taking was started in �・Key points: nuclear effects in R(NC/CC), Q2 extrapolation2014/02/9@KEK-TOKAI37

Summarygiven at workshops in 2007YAMAGATA UNIVERSITYΔs measurement at J-PARCAim to measure NC cross section on H, not R(NC/CC)Sensitivity study based on1E21POT neutrino off-axis beam at 280m away from the productiontargetDual SciBath detector (BC501A and BC533)δ(Δs) 0.03 expected (with dipole form factor assumption)Normalization and background contributions to the systematic error tobe studied.Q2 extrapolation (Q2 dependence) also has to be carefully studied.Normalization, Background (especially “Dirt”)has to be under control. Systematic is Key!2014/02/9@KEK-TOKAI38

YAMAGATA UNIVERSITY2014/02/9@KEK-TOKAI39

Neutrino flux information is needed to extract the cross section. n-H scattering extraction Using two targets with different mixture of H and C Separation of n-H and n-C scattering becomes possible Neutrino flux information is needed to extract the cross section. R(NC/CC) measur