中国与RHICSAR的国际合作

中国与RHIC-STAR的国际合作

马余刚，陈宏芳，程建平

中国RHIC-STAR合作组：中国科大，清华大学，上海应物所，华中师大，高能所，近物所2005/6/28-292005/6/28-29outlineChineseRHIC-STARGroupTOFrandPhysicsResultsImpactofChineseRHIC-STARGroupPhysicswithFullTOFProjectConclusion2005/6/28-29ChineseRHIC-STARGroup--Historyandpresentorganization2005/6/28-29US-ChinaCollaborationonSTAR/RHICASTAR-Chinacollaborationhasbeenestablished(SixInstitutionsfromChina)UniversityofScienceandTechnologyofChina,Hefei(USTC)TsinghuaUniversityShanghaiInstituteofAppliedPhysics(SINAP)CentralChinaNormalUniversity,Wuhan(CCNU)InstituteofModernPhysics,Lanzhou

(IMP)InstituteofHighEnergyPhysics,Beijing(IHEP)Chinesecollaboratorsareplayingamajorroleinphysicsanalysesinvolvingopencharm,Cronineffect,andellipticflowaspartofSTAR’sfocusonstudiesofanewstateofmatter(thequark-gluonplasma)atRHICChinesegroupsareleadinginprototypinganddevelopmentforalarge-areaMRPCtime-of-flightdetectorforSTAR.ThisisthefirstmajorUS-Chinacollaborationonhighenergynuclearphysicsandwehavehadaverysuccessfulbeginning.TheSTAR-ChinaTime-of-FlightConstructionProjecthasbeencoveredundertheUS-PRCHEPAgreementsince2001toensuresmoothconstructionoftheTOFdetectorandoperationoftheSTAR-Chinacollaboration.2005/6/28-29MajorMilestonesofSTAR-ChinaTOFProjectCCNUandIHEPjoinedSTARcollaborationin1999forTOFp;SINAP,USTC,TsinghuaandIMPjoinedSTARcollaborationinOct.2001.USTCteambeganMRPCR&DinAug.2000withthesupportsofNSFC,STARandotherChinesecollaborationinstitutions.JoinedinUS/PRCCooperativeAgreementonHighEnergyPhysicssince2001(22ndMeeting)PrototypeMRPC(multi-gapresistiveplate)time-of-flightdetectors,producedjointlybetweenUSTCandRiceUniv.andoperatedsuccessfullyinSTAR(2002-3and2003-4RHICruns).Physicsresultsonidentifiedparticlespectraandonsemi-leptoniccharmdecayshavebeenpublished.Approvalof"RHIC-STARPhysicsandtheConstructionofBarrelSTAR-TOF”bytheNationalNaturalScienceFoundationofChina(Sept10,2004,Budget:1.5MUSD)ApprovaloftheSTARTOFupgradeproposalbyBNLTechnicalAdvisoryCommitteeandSubmissionoftheProposaltoDOE(July2004)TechnicalReviewofproposalbyDOE,plannedAug.2005SupposeDOEapprovalinOct.2005,fullconstructionstartOctober20052005/6/28-29MRPCTOFBarrelR&DRUN2002-3:TOFinstalledinSTAR24MRPCmodulesproducedatUniversityofScienceTechnologyChina6-channelfront-endcards,withamplifiersanddiscriminators,CAMACread-outRun2003-4:TOFinstalledinSTAR5newmodulesfromUSTCand5fromTsinghuaUniversity,Tsinghuadevelopedautomatedtechniquesformanufacturing24-channelfront-endcardswithamplifieranddiscriminatorRUN2004-5,TOFinstalledinSTAR,

16newmodulesfromTsinghuaFirsttimeuseoffullon-boardread-outelectronics:digitizationofdataon-boardFirstuseofALICEPCI-PCbasedDAQ20022004G.Eppleyetal.2005/6/28-29CompletedPrototype28moduleMRPCTOFTrayinstalledinSTAROct.‘02inplaceofexistingcentraltriggerbarreltrayNeighborCTBTrayEMCRailsFEEMRPCdesigndevelopedatCERN,builtinUSTC/ChinaPrototypeTrayConstructionatRiceUniversity28MRPCDetectors;24madeatUSTCTheSTARBarrelTOFMRPCPrototype

70ps,2meterpathStrongteamincluding6ChineseInstitutionsinplace2005/6/28-29batchproduction40MRPCproduction，morethan80％ofeligiblerate,goodperformanceinon-linetestingatRHIC-STAR(Tsinghua)2005/6/28-29ProjectLeader:Yu-GangMa(SINAP)DeputyLeaders:HongfangChen(USTC) Jian-PingCheng(Tsinghua)Liaisonperson:HuanzhongHuang(UCLA)Studiesofthestronginteractionmatterathightemperature/densityandsearchingforQGP(Yu-GangMa,SINAP)(SINAP,CCNU,USTC,Tsinghuaetc.)

focusonthecollectivedynamicsofrareparticles,heavyquarkproduction,hadronicevolutiondynamicsandsearchformulti-quarkstateparticlesDesignandMassproductionofMRPCmodulesforSTAR-TOF(Jian-PingCheng,Tsinghua)(Tsinghua,USTC)

3840MRPCfor120tray,additional6tray(70%Tsinghua/30%USTC)QualitycontrolandcalibrationforSTAR－TOF(Xiao-LianWang,USTC)(USTC,Tsinghua)ChineseProposaltoNSFC2005/6/28-29TheProposalofRHIC-STARFullTOFConstructionProposedmajorconstructionresponsibilities:

ChineseSTARGroups:

MRPCProductionandQualityAssurance–NSFC/CAS/MoST(ApprovedinSept,2004)

(SpecialthanksforHuanzhong,Nu,Zhangbu,Xinnianetal.formanyimportantsuggestionsandhelps)USSTARGroups:

ElectronicsandIntegrationetc–DOEProjectManager:G.Eppley

(withDOE)MonetaryContributions:

China~US$2.5M(US$1.5MfromNSFC/CAS/MoST)US-DOE~US$4.5M2005/6/28-29STARTOFrandPhysicsResultsTOFprototype:1/120coverageofBarrelSTAR2005/6/28-29PIDTPCalonePIDrange:pi/k~0.6GeV/c,(pi,k)/p~1.5GeV/c;TOF““alone””PIDrange:pi/k~1.6GeV/c,(pi,k)/p~3.0GeV/cm2m2TOF=110pskpTPCaloneTOF““alone””2005/6/28-29PreliminarypionspectratillhighpTTPC:Pion:0-~0.6GeV/cKaon:0.2-~0.6GeV/cProton:0.2-~1GeV/cTOF:Pion:0.2-~1.6GeV/cKaon:0.2-~1.6GeV/cProton:0.2-~3GeV/cTPC+TOF:Pion:0.-~10GeV/cKaon:0.2-~3GeV/cProton:0.2-~5GeV/cTPC+TOF:2005/6/28-292005/6/28-29ElectronidentificationCombinedwithTOF，electronscanbeseparatedfrompionscleanlyElectornsmixedwithpionsifonlydE/dxofTPCisusedtoidentifyparticlesX.Dong,Z.B.Xu,LJRuan,JWuetalLeptondecayfromheavyquark2005/6/28-292005/6/28-292005/6/28-29RAuAuandRdAuoffRdAuofisclosertothatofpandkthanthatofpParticleproductionatintermediatepTregionissortedbytheparticle’stype,notthemassSTARPreliminary______________2005/6/28-29Preliminaryresultsv21.theellipticflowofΦ-mesongivessimilarbehaviorofKsbutdistinguishfromΛ2.aNCQ-scalinghasbeenobservedinΦ-meson3.errorbarsinhigtptrange(2.5GeV,5.0GeV)arestilllarge0-80%STARPreliminarydataAMPTcalc.2005/6/28-29ImpactofChineseRHIC-STARCollaboration2005/6/28-29OrganizingInternationalworkshopHost:Aug2002:1stInternationalCCASTSummerSchoolandWorkshopon““QCDandRHICPhysics”inCCAST-WL,Beijing.OrganizedbyProfs.X.L.WangandP.F.Zhuang.Therewere~15foreignspeakersinvited,~100participantsOct2003,1stSTARRegionalCollaborationMeeting,USTC;~10STARspeakersinvitedAug2004:2ndInternationalCCASTSummerSchoolandWorkshopon““QCDandRHICPhysics”inCCAST-WL,Beijing.OrganizedbyProfs.Y.G.Ma,E.K.WangandJ.H.Fu.Therewere19foreignspeakersand22domesticspeakers,~140participants.Oct2004:InternationalWorkshopon“CollectiveDynamicsinRelativisticHeavyIonCollisions”@USTC,OrganizedbyX.L.WangandNuXu19－24June2005:3rdInternationalWorkshopon““QCDandRICHPhysics”wasorganizedbyCCNUandCCASTetal.,,Wuhan;20foreignspeakers,~140participants2005/6/28-29Talk@Int.ConferenceQM2006inShanghai:Theproposaltohost““QuarkMatter2006”inShanghaiwasacceptedduringQM2004inOakland.ShanghaiInstituteofAppliedPhysicsandCentralChinaNormalUniversitywillco-organizetheQM2006inShanghai,preliminarydateNov16-22,2006Co-chairs:ZhiyuanZhu(SINAP)&XuCai(CCNU)HonorChair:T.D.LeeTaksinsomeinternationalconferences:ConferenceTalks:QM2004:oneoralpresentation(Ruan)SQM2004:threeoralpresentations(Cai,Ruan,Ma)ICEHP2004:oneoralpresentation(Wu)QM2005:onePlenaryTalk(Dong,fromTOFphysresults)oneparalleltalk(Cai)………2005/6/28-29OurexcellentstudentsPhDDissertations(incompletestatistics):JinghuaFU(CCNU):获二○○五年全国优秀秀博士学位论论文ShengliHHUANG(USTC),LijuanRUAN(USTC)，ZhixiLIU(CCNU)XingDONG(USTC):获二○○四年中国科学学院院长奖学学金特别奖MorePhDStudentsareinvolvedinRHIC-STARphysicsChinesePrincipalauthorsofSTARPublicationsorworks:JinghuaFuetal.:FlowofKsandfor130GeV/cAu+Au(Phys.Rev.Lett.89,132301(2002).)XinDongetal.:electronspectrafroopenCharm(nucl-ex/0407006),PRL94,062301(2005)LijuanRunetal.:CroninEffect(nucl-ex/0309012),PhysLettB616,8(2005)LijuanRuan(fortheSTARCollaboration),π,K,pandproductionfromAu+Aucollisionsat62.4GeV,J.Phys.G:Nucl.Part.Phys.31S1029-S1033(2005)XiangzhouCai(fortheSTARCollaboration)ProductionofK0s,ΛandΞfrom200GeVd+AucollisionsatRHIC,J.Phys.G:Nucl.Part.Phys.31S1015-S1018(2005)MingShao,Pion,Kaon,and(Anti-)ProtonProductioninAu+AuCollisionsat\srt=62.4GeV,J.Phys.G31(2005)S85-S92ShengliHuangetal.:azimuthaldependentfluctuationZhixuLiuetal.:flowofKsandfor63GeV/cAu+AuGuoliangMaetal.:flowandspectraoffor6363GeV/cAu+AuJinhuiChenetal.,phiflowJiaxuZuoetal.,multi-strangepartcilespactra,…………….2005/6/28-29PhysicswiththefullcoverageofTOF2005/6/28-29STARTPC+TOF(MC)Central(top10%)collisionsacceptancewithTPC:p:~60%K:~60%p:~50%acceptancewithTPC+TOF:>95%forallparticlesS/Nforfreconstructionwillincreasebyafactorof5-10v2measurementpossibleZ.Liu,F.Liu,etal.2005/6/28-29STARTPC+TOFTOFwillincreaseV0reconstructionefficiency.InthecaseofW,afactorof5––10increaseexpectedintheregionpT~3-5GeV/c!TOFwillalsohelpfutureDmesonreconstruction–increasingS/Nratios,samewayforotherresonances.(D0→K−+)(D0-bar→K+−)3)Inthecaseforf,afactorof5-10increaseinS/Nratioisexpected.=>K++K-(49.1%)H.Longetal.2005/6/28-29STARTPC+TOFWv2measurementsForintegratedWv2:needs~few106MiniBiasevents.MoreeventswithoutTOFMulti-yearsrunning.pTdependenceWv2:for<20%aroundpT~5GeV/c,needs~few10th106MiniBiaseventswithTOFalmostimpossiblewithoutTOFinmiddlePtSTAR200GeVresults:T=0.45GeVdN/dy=0.64,sumofW-andW+<v2>~8%allareusableevents(1.5-3factor)idealWithTOFw/oTOF2005/6/28-29TOFandHyperonEmbeddedData:LreconstructionwithandwithoutPIDinformation!AFactorof3!!Inputspectrum:T=350MeV2005/6/28-29ChineseinterestsCollectivedynamicsforrareparticlesHeavyflavorquarksSearchformulti-quarkstateparticlesFluctuationsCorrelationofrareparticlesHadronicevolutiondynamics:resonance…….2005/6/28-29Collectiveflowinpartoniclevel:DoestheRecombinationmodelworkforheavyparticlesorstrangequark?howaboutflowofelectron,,,D,J/v2(p)?NeedFullTOFforgoodefficiencyandstatistics2005/6/28-29WithoutTOFWithTOFAllpT12M2.6MpT>2.59M23M2>pT>4.85M42M4>pT>6.115M115MD0SensitivityinpTImportantMeasurement:OpenCharmTOFhelpsbyafactorof~5(allPT)TOF+ActivePixelSensitive:x8OtherOpenCharmStatesPossibleonlywithTOFFullCoverageneededHeavyflavorquarkInitialconditionJ/suppressionHeavyquarkenergylossCharmquarkmostlyproducedfromtheinitialfusionofpartons(mostlygluons)2005/6/28-29TimescaleofresonancestateResonanceK*(892)(770)f0(980)(1020)(1232)(1520)(1385)DecaychannelKKKeeppKResonanceParentPT(GeV/c)TPC+TOFK*00-12.0K*01-21.85K*02-31.74K*03-51.39______________________(1020)0-25.0(1020)2-53.42___________________________ChemicalFreeze-out---formationofhadronsKineticFreeze-out---InteractionceasesIncreasingfactorforstatisticalsignificanceofthesignalHadronevolutiondynamics：resonance2005/6/28-29DiscoveriesfromUnexpectedAreas?!RHIC--Frontierforbulkpartonicmatterformation(quarkclusteringandrapidhadronization)--Factoryforexoticparticles/phenomenaPotentialexoticparticles/phenomena: penta-quarkstates(uudds,uudds!) di-baryons H–(L-L,uuddss) [W-W](ssssss) strangequarkmatter…….penta-quarkstates?2005/6/28-29Searchformulti-quarkstateparticlesZ.Y.Zhangetal.,Phys.Rev.C61,065204(2000);Phys.Rev.C66,015205(2002)3bodydecay：2bodydecay：AchrialSU(3)modelandanalysesofthesymmetrypropertiesoftwo-baryonsystems,somefeatures:Adeeplybound,Eb~100MeV;Acompactobject,Rrms~0.63fm,<<Rdmaybesixstrangequarkstateratherthanadi-baryonconfigurationPhenomenologicalestimation(coalescence/statistical):yield10-4_10-7/centralAu-Au;FullbarrelTOF~100McentralAuAueventsneeded.Itisimpossibletosearchdi-omegainRHICwithoutSTAR-TOF2005/6/28-29ConclusionWehavestrongteamtocollaboratewithRHIC-STAR,especiallywehaveexcellentyoungstudentsandexcellentoverseasChineseAmericansChineseProposaltomakeB35arrelTOFhasbeenapprovedbyNSFC,weareplayingleadingroleinSTARTOFupgradeWehavegreatopportunitytodosomenewandimportantphysicswithfullTOF2005/6/28-29QuarkConfinement？RecallShanghaiTOFmeetingforDiscussionofNSFCproposaldraft,Jan20032005/6/28-29别有洞天Wehaveanewscenery!2005/6/28-29TraditionalCroninEffectisnotthewholestoryatRHICSTARd+AufromTOFranalysis(USTC