Recent results on light hadron/atBESspectroscopy董燎原(forBESCollaboration)中国科学院高能物理研究所中国物理学会高能物理分会April 17-19 2010
Recent results on light hadron spectroscopy at BES 董燎原 (for BES Collaboration) 中国科学院高能物理研究所 中国物理学会高能物理分会 April 17-19 2010
OutlineIntroduction ofBES atBEPCIntroduction of Light hadron physics at BESllObservation of charged k at BESllConfirmation of ppbar mass thresholdstructure at BESlllConfirmation of X(1835) at BESIlSummary22010/4/18
Outline ⚫ Introduction of BES at BEPC ⚫ Introduction of Light hadron physics at BESIII ⚫ Observation of charged at BESII ⚫ Confirmation of ppbar mass threshold structure at BESIII ⚫ Confirmation of X(1835) at BESIII ⚫ Summary 2 2010/4/18
BeijingElectronPositron(BEPC)at IHEPCollider(LinacStorageringBESBSRFBESI:BeijingSpectrometerI:1989-1998BESII: 1999-2004 L~ 5*1030cm-2s-1@ J/y Ebeam~ 1-2.5GeVBESIII:2008 (Physicsrunfrom March2009)-,L~3.2*1032cm-2s-1@y(3770)~30%ofdesignedvalue3
Beijing Electron Positron Collider (BEPC) at IHEP BESI: Beijing Spectrometer I : 1989 -1998 BESII: 1999 - 2004 L ~ 5*1030cm-2s-1@ J/ Ebeam~ 1-2.5 GeV BESIII: 2008 (Physics run from March 2009)- , L~3.2*1032cm-2s-1@(3770)~30% of designed value 3
BESII@BEPCBESII@BEPCIIMUCECALSMOCOSQ=0.93UOFMDCMDCVertexchamber国中-Superconducting magnetBESIIBESIIIMDCo(p)/p= 1.78%·V1+p2o(p)/p, = 0.32 % PtdE/dxreso = 8 %dE/dXreso < 6 %TOF18ops(forbhabha)gops(forbhabha)EMCO(E)/E=22%·VEO(E)/E=2.3%-VEMUC3 layers for barrelg layers forbarrel, 8 for endcap
4 9/17/2026
Milestones of BESlllPeakLumi.@NovMar.2008:firstfull cosmic-ray event2008:April30,2008:MovetheBESllltoIP1.2×1032cm-2s-1July19,2008:FirstetecollisioneventinBEslllPeakLumi.@MayNov.2008:~14M(2S)eventscollected2009:April14,2009~110Mw(2S)eventscollected(x4CLEOc3.2×1032cm-2s-1May30,200942pb-1atcontinuumcollected@y×5CESRcJuly28,2009~220MJ/yeventscollected(x4BESll)×30BEPC5
Milestones of BESIII 5