StatusofBESlllWeidong LiIHEP, CAS, BeijingNanchang17th April, 2010
Status of BESIII Weidong Li IHEP, CAS, Beijing Nanchang 17th April, 2010
BEPCll Storage Ring.SR..RERE...Beamenergy:1.0-2.3 GeVLuminosity:3~10×1032cm-2s-Optimumenergy:1.89GeVEnergy spread:5.16 X10-4No.of bunches:mrad938ns2Bunch length:1.5cm2.5m1.5cmTotalcurrent:0.91ASR mode:0.25A@2.5GeVIP
RF SR RF IP 22 mrad 2.5m 8ns 1.5cm 0.1cm Beam energy: 1.0-2.3 GeV Luminosity: 3~10×1032 cm-2s-1 Optimum energy: 1.89 GeV Energy spread: 5.16 ×10-4 No. of bunches: 93 Bunch length: 1.5 cm Total current: 0.91 A SR mode: 0.25A @ 2.5 GeV BEPCII Storage Ring 2
BESlllDetectorMianDriftChamberSuper-conductingmagnet(MDC)1.0tesla△P/P(%)=0.5-0.7%(1 GeV)CdE/dx (%)= 6-8%Time Of Flight(TOF)μCounterr (ps)=100-120 ps Barrel-8-9layers110-130 ps endcap8R@Φ=1.4cm~1.7cmEMC: △E/NE(%)=2.5-3% (1GeV)z,(cm)=0.5cm-0.7cm/VE3
BESIII Detector μCounter 8- 9 layers R=1.4 cm~1.7 cm Time Of Flight (TOF) T (ps)=100-120 ps Barrel 110-130 ps endcap Mian Drift Chamber (MDC) P/P (0 / 0 ) = 0.5-0.7 % (1 GeV） dE/dx ( 0 / 0 ) = 6-8% EMC：E/√E(0 / 0 ) = 2.5 -3 % (1 GeV) z, (cm) = 0.5cm-0.7 cm/√E Super-conducting magnet 1.0 tesla 3
4BEPCI/BESIlICommissioningmilestonesOct.25-31.2007:accumulationofelectron/positronbeamsNov.18.2007:firste+e-collisionwithoutBESllldetectorMar.2008:Collisionat500 mA X 500 mA,Lumi.:1 X1032cm-2s-1Mar.2o08:firstfullcosmic-rayeventinBESIllApril30,2008:MovetheBESIlltoIPJuly18,2008:Firste+e-collisioneventinBES1llNov.2008:Lumi.~1.2x1032cm-2s-l,BESIll~10M(2S)eventsApril14,2009 BESIlI~100M y(2S)events(~40 days)1032cm-2s-1May14,2009BEPCIILumi.~3July28th2009BESIII~200MJ/y
BEPCII/BESIII Commissioning milestones Oct. 25-31, 2007: accumulation of electron/positron beams Nov. 18, 2007: first e+e- collision without BESIII detector Mar. 2008: Collision at 500 mA × 500 mA, Lumi.: 1 ×1032 cm-2 s -1 Mar. 2008: first full cosmic-ray event in BESIII April 30, 2008: Move the BESIII to IP July 18, 2008: First e+e- collision event in BESIII Nov. 2008:Lumi. ~1.2 1032cm-2 s -1 , BESIII ~ 10M (2S) events April 14, 2009 BESIII ~100M (2S) events (~40 days) May 14, 2009 BEPCII Lumi. ~ 3 1032cm-2s-1 July 28th, 2009 BESIII ~200M J/ Ψevents (41 days) 4
FirstHadronicEventRun4530BesOisEvent100893date.2008-07-26找me：8764.04MC=NoP=3.116GeVPt=2.903GeVtofMin=0.000nsECal=1.082GeVMDCTrack(GeV)P1=0.945P2=0.702P3=0.421P4=1.048EMCChuster(MeV):E1=151.91E2*226.00E3-295.91E4=165.27E5=48.68E6193.98xywiewZRUiew
First Hadronic Event 5