一般化されたパートン分布関數(shù)：実験の現(xiàn)狀東工大柴田利明

Sept27,2004

atKochi,JPST.-A.Shibata一般化されたパートン分布関數(shù)：実験の現(xiàn)狀目次1.陽子のスピン構(gòu)造、一般化されたパートン分布関數(shù)2.実験の現(xiàn)狀、ExclusiveProcess

(排他的過程）3.電子散亂－DeeplyVirtualComptonScattering（深仮想コンプトン散亂）4.ニュートリノ散亂5.展望とまとめT.-A.ShibataIntroduction:SpinofProtonSumofSpinsofuudQuarks=SpinofProton++SU(6)QuarkWaveFunctionsofBaryons1/21/2-1/2

1/2EMCExperiment(1988)20–30%ofNucleonSpin=‘NucleonSpinProblem’T.-A.ShibataEMC+Neutronlifetime

HyperonweakdecaysflavorSU(3)symmetryassumed0.20.40-0.2-0.4sum1/2T.-A.ShibataCERNEMC,SMC,COMPASS160GeV

pol

p,dDISDESY-HERAHERMESe28GeV

pol

p,dDISSLACe50GeV

pol3He,p,dDISJLAbHallAe6GeV

pol3HeDISHallBe6GeV

pol

p,dResonanceReg.HallCe6GeV

pol

p,dResonanceReg.MIT/BatesSAMPLEe0.2GeV

p,dElasticScatt.PVJLABG0e6GeV

p,dElasticScatt.PVJLABHAPPEXe6GeV

p,dElasticScatt.PVMainz-MAMIe0.88GeV

p,dElasticScatt.PVBNL

E734

1.3GeVpElasticScatt.NCBNL-RHICPHENIXp+p200or500GeVgluonspin,seaquarkSTARp+p200or500GeVgluonspin,seaquarkKEKB-factoryBELLEe+e,8on3.5GeVfragmentationfunction

ColliderExperiments:FixedTargetExperiments:ExperimentsontheProtonSpinandrelatedmeasurementsT.-A.ShibataDeepInelasticScattering,Semi-inclusiveMeasurements

Semi-inclusivemeasurement,

e’and

(quarkdistribution)x(fragmentationfunction)ee’FlavortaggingInclusivemeasurement,e’Factorization:T.-A.ShibataOFFFORWARDPARTONDISTRIBUTIONSX.D.Ji,J.Phys.G24(1998)1181-1205158

DEEPLYVIRTUALCOMPTONSCATTERINGX.D.Ji,Phys.Rev.D55(1997)7114-7125415…..Theory:

forexample,T.-A.Shibata

Generalized(Off-Forward)PartonDistributionsGeneralizedPartonDistributions(GPD)DeepInelasticScatteringDeeplyVirtualComptonScatteringElectromagneticFormFactors(ElasticScattering)TotalAngularMomentumJqExclusiveMesonProductionOrbitalAngularMomentum

LqT.-A.Shibata

Generalized(Off-Forward)PartonDistributionsSumrules,

x–integral,sumoverq

DiracandPauliNucleonFormFactors

Axial-vectorandPseudo-scalarFormFactorsOrdinaryQuarkDistributionsForwardlimitTotalangularmomentumOrbitalangularmomentum2ndmomentT.-A.ShibataExperimentalMethodsandResultsT.-A.ShibataQuarkHelicityDistributions,FlavorSeparationDouble-spinasymmetryBeamandtarget,bothpolarizedNucleonVirtualphotonPolarizede,1994T.-A.ShibataｘpositivenegativeA1HERMES(2004),hep-ex/0407032

T.-A.ShibataFlavorSeparation,

QuarkHelicityDistributionsResult:x

QCDfitstoinclusivemeasurements

Xbinbybinanalysisexceptforsmearingcorrection.

Nofunctionalformsareassumed.Nofirstmomentsareassumed.

HelicityconservationnotassumedHERMESxErrorband–systematicerrorT.-A.ShibataDeeplyVirtualComptonScattering「HERMESによるHardExclusive生成過程の測定：一般化されたパートン分布関數(shù)による核子構(gòu)造の研究」宮地義之、柴田利明、高エネルギーニュース,22(2003)11http://www-he.scphys.kyoto-u.ac.jp/~nakaya/HEPNews/T.-A.ShibataInclusiveMeasurement:Totalcrosssectionforvirtualphoton–nucleonreactionT.-A.Shibata

DeeplyVirtualComptonScattering(DVCS)

--ExclusiveproductionofarealphotonDeeplyVirtualComptonScatteringGPDImCosssectionforinclusivedeepinelasticscattering:Lightconemomentumfraction:Exchangedlongitudinalmomentumfraction:MomentumtransferT.-A.ShibataDeeplyVirtualComptonScatteringBeam-spinasymmetrybyHERMESandCLASBeam-chargeasymmetrybyHERMES--DVCS-BHInterference,RealandImaginaryDeeplyVirtualComptonScatteringBethe-HeitlerProcess,knowncalculableDVCSCrossSectionbyZEUSandH1HowtomeasureDVCST.-A.ShibataHERMES(DESY)CLAS(JLab)DeeplyVirtualComptonScatteringFirstobservationofbeam-spinasymmetryofDVCS

~30%effectT.-A.ShibataBeam-SpinAsymmetryDeeplyVirtualComptonScattering,GeneralizedPartonDistributionsHERMESMissingMassResolution0.8GeVT.-A.ShibataHowtoextendGPDGPDQuantumnumberoffinalstateSelectdifferentGPDPseudoscalarmesonVectormesonExclusiveMesonProductionsHERMES’sdataT.-A.ShibataNeutrinobeamexperimentsT.-A.Shibataneutrino-protonelasticformfactorandHowtomeasure:T.-A.ShibataNeutrino-nucleonelasticscatteringcrosssectionfromviewpointofstrangequarkspinintheproton

BNL734experimentwithNeutrinobeamfromAGSonproton,(meanenergy1.3GeV),(1.2GeV)E734L.A.Ahrensetal.,Phys.Rev.D35(1987)785,G.T.Garveyetal.,Phys.Rev.C48(1993)761FINNeSSEatFNALandBNL,ExperimentatJ-PARC(NP04,Aug.2004)T.-A.ShibataNeutrinoFluxatJ-PARC,50GeVproton,at280mT.-A.ShibataSummaryandOutlookManyexperimentsonSpinStructureoftheProtonaregoingonandareplannedallovertheworld.Genaralized(Off-Forward)PartonDistributionisa‘GrandUnifiedTheory’ofHadronsPartonDistributionq(x),FormFactors,andexcluiveprocessescanbeanalysedinthesameframework.DeeplyVirtualComptonScattering,inparticularitsspindependence,hasbeenmeasured.Page1T.-A.ShibataFormFactorsfromNeutrinoScatteringareimportantelements.ExclusiveProcessofHadronReactions(gluonComptonscattering,2jetproductio