双重子研究的一些新进展课件

Multi-StrangenessDibaryonT.Goldman,TD,LANLY.X.Liu,PekingUniv.X.F.Lu,SichuanUniv.J.L.Ping,NanjingNormalUniv.FanWang,NanjingUniv.Multi-StrangenessDibaryonT.G1Contents“Discovery”ofmulti-quarkstates.Candidatesofmulti-strangenessdibaryons.RHICisafactoryofmulti-quark.NonperturbativeQCDbasisofquarkmodels.ProposalContents“Discovery”ofmulti-q2“Discovery”ofMultiquarkThe“discovery”ofmultiquarkstatessetschallengesaswellasopportunitiestoquarkmodels.

Elevengroupsclaimedthattheyobservedapentaquarkstate,calledΘ+:

Θ+:I=0,J=1/2,Parity=?,M=1540MeV,Γ≤25MeV,NA49Ξ--:I=3/2,M=1862MeV,Γ≤18MeV,H1Θc:I=0,M=3099MeV,Fourgroupsclamedthattheyobservedtetraquarkstates.Uptonownodibaryonorhexaquarkstatehasbeenobserved.IfthePendoraboxofmultiquarkreallyhasbeenopened,allofthesemultiquarkstatesshouldappearsoonerorlater.Thediscoveryofmulti-quarkstatessetschallengesaswellasopportunitiestoquarkmodels,evenlatticeQCDandothers.FourlatticeQCDcalculationsgavetotallydifferentresults.Therehavebeenmorethan200papersaboutpentaquarkbutnoconsensusyet.“Discovery”ofMultiquarkThe3CandidatesofDibaryonsCandidatesofMulti-StrangenessDibaryons.

ChiralsolitonquarkmodelpredictionoftheΘ+playedavitalroleinthe“discovery”ofΘ+.

Quarkmodelpredictionsofdibaryon:1.H(uuddss)I=0,Jp=0+,S=-2WangZhangothersThresholdM(MeV)22282223deeplybound223122302233tounbound(2230-32)Quiteimpossibletobedeeplybound.Morethan25yearssearchwithnullresult.CandidatesofDibaryonsCandid42.

I=0,Jp=0+,S=-6WangZhangOthersThresholdM(MeV)32983229deeplybound334533003292tounbound(3300-4)SimilartoHparticle,weaklyboundorunbound.2.I=0,Jp=0+,S=-653.N

I=1/2,Jp=2+,S=-2WangZhangOthersThresholdM(MeV)25492561deeplybound261125572607tounbound(2590)

(keV)12-22DecaymodeN

-->

1D2,3D2.Quitepossibleanarrowresonance.(Wang:PRL59(87)627,69(92)2901,PRC51(95)3411,62(00)054007,65(02)044003,69(04)065207;Zhang:PRC52(95)3393,61(00)065204,NPA683(01)487.)3.NI=1/2,Jp=2+,S=-26RHIC,amultiquakfactoryRHICisafactoryofmultiquarkstatesespeciallymultistrangenessdibaryons.

Highstrangenessproduction.Hadronizationandclusteringattheboundaryoffireball.Shandonggroupestimation:noproblemtoproduceNinoneevent,buthardtohaveinoneevent.RHIC,amultiquakfactoryRHIC7NonperturbativeQCDbasisofquarkmodelsNonperturbativeQCDbasisofquarkmodels.

Howreliablearethesequarkmodelpredictions?Wang(QDCSMorNanjing-LosAlamosmodel)Zhang(chiralquarkmodelorTokyo-Tuebingen-Beijing-Salamankamodel)bothfittheexistedNBscatteringdata(Zhang’sbetter)anddeuteronproperties(Wang’sbetter).

TheeffectiveattractiondevelopedinandNchannelsisquitemodelindependent.

TherearemanyotherquarkmodelsbutIwillnottalkaboutthemhere.

NonperturbativeQCDbasisofq8Quark-GoldstonebosoncouplingFromcurrent-quarkgluonQCDtoconstituentquarkGoldstonebosoneffectivetheory

‘tHooft-Shuryak-Diakonovdiluteinstantonliquidvacuum(DILM).(NPB203,245,461)Negele’slatticeQCDsupportsDILM(fig.1).(PRD49(94)6039)OurgroupreproducedpartofNegele’sresult.IthasnotbeenprovedbutmightbeagoodapproximationofQCDvacuum.Quark-Goldstonebosoncoupling9双重子研究的一些新进展课件10CurrentquarkpropagatingwithintheDILM(fig.2)(NPB272(86)457;hep-ph/0406043)

CurrentquarkmisdressedtobeconstituentquarkM(q2)(fig.3)TheQCDLagrangianistransformedtobetheeffectiveLagrangian

Currentquarkpropagatingwit11双重子研究的一些新进展课件12OurgroupderiveaneffectiveLagrangianbasedonchiralsymmetryspontaneouslybrokenanditsnonlinearrealization,

Theconstituentquarkfieldoperator

cisrelatedtothecurrentquarkoperator

byOurgroupderiveaneffectiv13

TheformofdynamicallyderivedeffectiveLagrangian,suchastheformerDiakonov’sLagragian,ismodeldependent,butthenonlinearcouplingisdictatedbythechiralsymmetryspontaneouslybrokenaswedid.

ThelinearapproximationofZhang(NPA683(01)487)andothers,suchasGlozman&Riska,Phys.Reports,268(96)263,missedthehigherorderterms,whichshouldbeimportantforshortrangephysics,suchasmultiquarkstudy.

TheSU(3)extensionoflinearapproximationisevenquestionable,theuniversalu,d,s-σquarkmesoncouplingwilloverestimatetheσinducedattractionwithstrangenessparticles.Theformofdynamicallyderi14QDCSM

Nanjing-LosAlamosmodelQCDbasisofNanjing-LosAlamosmodelTheconstituentquark-GoldstonebosoncouplingeffectiveLagrangianisstillanonperturbativestronginteractionfieldtheory.Wedidaselfconsistentmeanfieldapproximationcalculationandfoundthattheself-consistentmesonmeanfieldincreasesastheincreasingofquarkexcitation,i.e.,themeanfieldtrytokeepthequarkconfined,withinalimitedexcitation.QDCSM

Nanjing-LosAlamosmod15双重子研究的一些新进展课件16QuenchedlatticeQCDcalculation(hep-lat/0407001andtheref.’stherein))showsthatthegroundstategluonfieldenergyforsystemscanallbeexpressedas

wheretheLministheminimumlengthofthegluonfluxtubeorstring.(fig.4)(hep-lat/0407Unquenchwillmodifythelongrangebehaviorbycolorscreening(fig.5).QuenchedlatticeQCDcalculat17双重子研究的一些新进展课件18Forindividualcolorconfiguration,thequenchedlatticeQCDresultcanbeapproximatelyexpressedbyatwobodyconfinementpotential,(NuovoCmento,86A(85)283)

Vij=-kλiλjrijpp=1,2,theunquenchedonecanbeapproximatedasVij=-kλiλjrijp(1-exp(-μrijp))/μ,p=1,2,

μiscolorscreeningconstant.Thesecolorconfigurationswillbemixedduetogluonfluctuationandexcitation.Forindividualcolorconfigur19

Inthenaïvequarkmodel,mesonandbaryonhaveuniquecolorstructure:

baryonmesonSoDeRujula,Georgi,GlashowandIsgurcanhavesimpleHamiltonianforhadronspectroscopy.Inthenaïvequarkmodel,mes20

Forpentaquarktherearemorecolorstructures:

……Forpentaquarktherearemo21

Inprincipleoneshouldhaveamultibodyinteraction,multichannelcouplingmodel.NumericallyitisquiteInvolved.Wedevelopedaquarkdelocalization,colorscreeningmodel(QDCSM),wherethemulticolorcouplingsaremodeledbyanextendedeffectivematrixelementswithinatwoclusterHilbertspacewherethecolorscreeningconstantμisleftasavariationalparameter;themultiquarkorbitalconfigurationsaremodeledbymeansofdelocalizedquarkorbitswithinatwoclusterspacewherethedelocalizationparameterεisleftasanothervariationalparameter.

Inprincipleoneshouldhave22

Thevariationalcalculationwillallowthemultiquarksystemtoadjustthemselvestoarriveataselfconsistency.

WecannotderivethismodelfromQCD.Thefitofhadroninteractiondatashowsthatthismodelcomprisesrightphysicsatleastpartly.

Thevariationalcalculation23ProposalHparticle:Atmostweaklyboundorunbound,keepitasacandidateatRHICsearch,butnotverypromised.Di-

Possiblyaweaklyboundstate,keepitasanothercandidate,buttheproductionrateisverylow.NThemostpromisedone,itisaverynarrowresonancearound2.55GeV,evennarrowerthantheΘ+.

Proposal24Thanks谢谢(xiexie)

Thanks谢谢(xiexie)25QDCSMHamiltonian:QDCSMHamiltonian:26RGM

RGM27

Wavefunctions:Wavefunctions:28ModelParametersM=313MeV,b=0.602fm,αs=1.555,a=25.03MeV/fm2,Ms=634MeV.r0=0.8fmarefixedbygroundstatemassesofbaryonsμ=0.9fm-2Isfixedbydeuteronproperties,shouldbeadjustedforeverymultiquarksystem.DelocalizationparameterεisdeterminedforeveryseparationandeverychannelbythedynamicsofthemultiquarksystemModelParametersM=313MeV,b=029DibaryonsDeuteron(Strangeness=0,I=0,J=1):Md=1875.8MeV,=1.92fm,PD=4.92%,two-baryonstateTheΔΔcomponentsofdeuteronisconsistentwiththeSalamancaresult.H(Strangeness=-2,I=0,J=0):FirstpredictedbyJaffein1977withMITbagmodel.MH=2228-2230MeV.Aweaklyboundorunboundone.DibaryonsDeuteron(Strangeness=30

d*(Strangeness=0,I=0,J=3):Md*=2165MeV,=1.3fm.(6-quarkstate