高能物理实验发展方向-PowerPointPresen

CDLu1PuzzlesornewphysicssignalinBphysics呂才典IHEP,BeijingCDLu2CurrentBphysicsexperimentsEnhancementofcolorsuppressedmodesDirectCPasymmetry/AnnihilationMixinginducedCPasymmetryPolarizationsinBVVdecaysSummaryOutlineCDLu3高能物理实验发展方向更高能量：Tevatron,LHC，ILC，––直接对新粒子，新物理的探索更高亮度：B工厂，tau－粲工厂等––精确检验，间接新物理的探索，更经济对超对称等新物理模型的参数限制大多来源于B物理实验肖振军、杨亚东有很多研究CDLu4KEKSLACCurrentBfactoriesBaBarPEPIIKEKBBelleCDLu5BFactoryExperimentsKEK,KEKB，e+8GeV,e–3.5GeVBelle:700MillionBB-barpairSLAC,PEP-II,e+9GeV,e–3.1GeVBaBar:400MillionBB-barpairTheycanreachbranchingratiosassmallas10–7rareBdecaysd’VudVusVubds’=VcdVcsVcbsb’VtdVtsVtbbUnitarityVudVub*+VcdVcb*+VtdVtb*=0Thetrianglesaremeasuredmainlythroughnon-leptonicB(bd)decaysForexample:αbyB→ππ,πρ,αβbyB→J/ψK,KVudVub*VtdVtb*γbyB→Kπ,Bs→Kρ,γβVcdVcb*CDLu7CurrentCKMmeasurements标准模型可以很好地解释目前的实验CDLu8CLEO实验组(已降能区)Belle@KEK和BaBar@SLAC工作在B物理的能区,现在正在取数.Tevatron实验室上也有很多Bs的数据2007年底即将运行的LHC-b筹划中Super-B......thesizeofCPviolationisnotbigenoughforcosmology实验状况CDLu9BpipidecaysModeExppQCD(LO)NLObudbuddduu0CDLu10BpipidecaysTree(T),colorsuppressedtree(C),penguin(P)CDLu11Twooperatorscontributetodecay:B00B00colorenhancedcolorsuppressedC1~–0.2~1/3C2~1/3bddbcdd0D0D)()(1dbcuO)()(2cbduO000DBcuuCDLu12IsospintriangleD+–(a1)D0+(a1+a2)D00(a2)LaterexperimentsfoundmuchlargerB0D0pi0branchingratiosCDLu13Fordecay,thesetwodiagramsdonotcancel000DBD+–(a1)D0+(a1+a2)D00(a2)47.02aarg(a2/a1)~–41°CDLu14BranchingratiosofBD(*)modesFac.APQCDEXP.D*+–292527.6±2.1D+–302730±4D*001.02.81.7±0.5D000.72.52.9±0.5D*0+485346±4D0+485453±5PQCD:Keumetal,PRD69:094018,2004a1=1.08a2=0.21forFact.Approach(x10–4)CDLu15DirectCPviolationcoscos21sinsin22rrrACP)()()()(BBBBACPCDLu16DirectCPViolationRequiretwokindsofdecayamplitudeswith:Differentweakphases(SM)Differentstrongphases–needhadroniccalculation,usuallynon-perturbativeCDLu17B→,KHaveTwoKindsofDiagramswithdifferentweakphasebWuTree∝VubVud*(s)Bd(s)(K)WbtPenguin∝VtbVtd*(s)BO3,O4,O5,O6O1,O2(K)CDLu18CDLu19StrongphaseisimportantfordirectCPButusuallycomesfromnon-perturbativedynamics,forexampleDKKKForBdecay,perturbativedynamicmaybemoreimportantCDLu20lXBubuCutquarkdiagram~Sumoverfinal-statehadronsnp,,,~On-shellOff-shellhadronsInclusiveDecayCDLu21pseudo-scalarBrequiresspinsinoppositedirections,namely,helicityconservationmomentumBfermionflowspin(thisconfigurationisnotallowed)p1p2Annihilationsuppression~1/mB~10%LikeBeeFor(V-A)(V-A),left-handedcurrentCDLu22NosuppressionforO6Space-likepenguinBecome(s-p)(s+p)operatorafterFiertztransformationChirallyenhancedNosuppression,contribution“big”(20-30%)b)(sddud+(K+)–CDLu23ChiralEnhancementTwopenguinoperators:O4~(V-A)(V-A)O6~(V-A)(V+A)bsqqtRqqLbdOq6LqqLbdOq4R,L=15Fiertztrans.O(1)(S+P)(S-P)2mK2/(msmB)CDLu24CPViolationinB(K)(realpredictionbeforeexp.)CP(%)FABBNSPQCDExp+K–+9±3+5±9–17±5–9.7±1.20K++8±27±9–13±44.7±2.6+K01.7±0.11±1–1.0±0.50.9±2.5+––5±3–6±12+30±10+38±7(2001)CDLu25BKpuzzleK+-andK+0differbysubleadingamplitudesPewandC.TheirCPareexpectedtobesimilar.Theirdatadifferby5!Apuzzle!ACP(K+pi–)=(–9.51.3)%ACP(K+pi–)=(4.72.6)%CDLu26Amplitudeparametrization(C2/C4)(VusVub/VtsVtb)»(1/2)(5/2)»CDLu27DirectCPviolationTexp(i3)PTexp(-i3)Texp(i3)PTexp(-i3)IfT=0BrBr=BrIfT=0Br=BrDirectCPRecallsinsinCPACDLu28Explanation1LargeK+-CPimplieslargeT(predictedbyPQCDin2000)LargePEWtocancelitseffect(Burasetal.;Yoshikawa)inK+0newphysics?Texp(i3)PTexp(-i3)PEWBr¼BrCDLu29Explanation2OrlargeCtocancelitseffect(CharngandLi;HeandMcKellar)inK+0)mechanismmissedinSMcalculation?(T+C)exp(i3)(T+C)exp(-i3)Texp(i3)PCDLu30CDLu31MixinginducedCPviolationCDLu32DeviationfromBJ/psiKsCDLu33CDLu342007resultCDLu35CDLu36MixingInducedCPB+–,K,’K,KKK…DominantbytheB-BbarmixingMostoftheapproachesgivesimilarresultsEvenwithfinalstateinteractionsCDLu37ForExample:(FromYossiNir)CDLu38PolarizationofBVVdecaysQCDF0.940.950.910.94CDLu39Newphysics(Grossman;Yangetal.;Giri,Mohanta;Dasetal.)AnnihilationeffectinQCDF(Kagan)CharmingpenguininSCET(Baueretal)Rescatteringeffect(Colangeloetal.;Ladisaetal.;Cheng,Chua,Soni)Exoticbsg(Hou,Nagashima)PlausibleresolutionsCDLu40PreviouspQCDRL=75%forBK*phiToolargeBrsthanexp.ImpliestoolargeformfactorSofar,nodata,exceptK*,controlA0B()K*aregovernedbyB()formfactors=A0forBK*couldbesmaller?ChoosetheasymptoticmodelsforthecorrespondingK*mesondistributionamplitudesA0=0.28CDLu41Annihilationcanenhancetransversecontribution:RL=59%(exp:50%)andalsorightratioofR=,Randrightstrongphase=,bsdsdLargetransversecomponentinBK*decaysK*H-nLi,Phys.Lett.B622,68,2005CDLu42PolarizationofBVVdecaysQCDF0.940.950.910.94Newphysics?CDLu43NewphysicsatTeVPromisinghypothesesthatpredictnewelementaryparticlesintheTeVscale(SUSY,extra-dimension,etc.)Moreambitiousproposalsthatincorporateflavorsymmetries(andviolation)toanswerthedeeperquestionsofflavorphysics.NewCP-violatingphasesandnewinteractionsofquarksandleptonsalmostexpectableCDLu44NewphysicsatTeVNewparti