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HADRON11, MunichJune 13-17, 2011Recent Results from the KEDR DetectorSimon EidelmanBudker Institute of Nuclear Physics,Novosibirsk, Russia′1. J/ψ and ψ massesOutline2. Parameters of ψ ′3. Parameters of ψ(3770)4. Search for narrow resonances5. ConclusionsS.Eidelman, BINPp.1/21
HADRON11, MunichJune 13-17, 2011VEPP-3VEPP–4M colliderVEPP-4MCircumference366 mBeam energy1 6 GeVNumber of bunches2 2Luminosity, E 1.5 GeV 2 1030 cm 2 s 1KEDRLuminosity, E 5.0 GeV 2 1031 cm 2 s 1 Resonant depolarization technique:Instantaneous measurement accuracy 1 10 6Energy interpolation accuracy (5 15) 10 6 (10 30 keV) Infrared light Compton backscattering:Statistical accuracy 5 10 5 / 30 minutesSystematic uncertainty 3 10 5 (50 70 keV)S.Eidelman, BINPp.2/21
HADRON11, MunichJune 13-17, 2011Compton Backscattering MonitorRealized at BESSY-I in 19872TSeamHPGe detector111111 000000000111000111000000 111111KEDR1lectron bTSVEPP 4MeTSTS34000111 111000000111000111000000 111111Compton photonstatLMCryosKEDRGEM Select 50CO2 laserS.Eidelman, BINPlaser beamp.3/21
HADRON11, MunichJune 13-17, 2011VEPP-4M Energy BehaviourVEPP-4M energy, MeVRDM measurementsCBS measurementsinterpolated /04During the run, E measured by CBS and from interpolationS.Eidelman, BINPp.4/21
HADRON11, MunichJune 13-17, 2011KEDR detector1. Vacuum chamber2. Vertex detector3. Drift chamber4. Threshold aerogel counters5. ToF counters6. Liquid krypton calorimeter7. Superconducting coil8. Magnet yoke9. Muon tubes10. CsI calorimeter11. Compensating s/c solenoidS.Eidelman, BINPp.5/21
HADRON11, MunichJune 13-17, 20111200σ , nbScan IV:σW 0.664 0.0181000obsobsσ , nbJ/ψ and ψ ′ Mass Measurement – IScans I,IIσW 0.8391500600Scan III:σW 0.900 0.02040010002000σW 0.698 0.0022000 0.0138002500500154615471548154915501551E, MeV0154415461548155015521554E, MeVMJ/ψ (3096.913 0.006 0.009) MeVMψ′ (3686.126 0.007 0.011) MeVS.Eidelman, BINPp.6/21
HADRON11, MunichJune 13-17, 2011J/ψ and ψ ′ Mass Measurement – II Systematic errors in mass measurements are the main issue More than 20 different effects considered Energy spread, energy assignment, energy difference of e and e ,beam misalignment, luminosity etc. No significant improvement for the J/ψbecause the additional scan had bigger systematicsS.Eidelman, BINPp.7/21
HADRON11, MunichJune 13-17, 2011J/ψ and ψ ′ Mass Measurement – III5KEDR 2003-20054KEDR 2003OLYA 19801-0.4-0.3-0.2-0.100.1OLYA 198010.20.3MΙ/ψ - 3097S.Eidelman, BINPE760 1993(using Mψ by KEDR)2SPEC 19872KEDR 20033E760 1993(using Mψ(2s) by KEDR)3KEDR 2003-20064-0.2-0.15-0.1-0.0500.050.10.15Mψ(2s) - 3686p.8/21
HADRON11, MunichJune 13-17, 2011Measurement of Γee · B(ψ ′ hadrons) for ψ ′ – Iσ [nb]800scan 1,σW 1.08 MeV700scan 2,σW 1.05 MeV600scan 3,σW 0.98 MeV5004003002001003675S.Eidelman, BINP3680368536903695W[MeV]p.9/21
HADRON11, MunichJune 13-17, 2011Measurement of Γee · B(ψ ′ hadrons) for ψ ′ – IISourceScan 1Scan 2Scan 3Common 1-2CommonLumin.1.61.71.21.60.4MC on0.50.30.60.30.3MC nucl.0.30.30.30.30.3Energy0.150.180.600.150.15MC vert. 2.11.92.01.1S.Eidelman, BINPp.10/21
HADRON11, MunichJune 13-17, 2011Measurement of Γee · B(ψ ′ hadrons) for ψ ′ – III Γe e · B(ψ ′ h) (2.245 0.015 0.036) keV,much more precise than the only previous direct measurement Using the world-average value of BhΓe e (2.294 0.015 0.037) keV,about 3 times better than the best previous one. Using the world-average values of Γe e and BhΓ (297 2 8) keV,again about 3 times better than the best previous one.S.Eidelman, BINPp.11/21
HADRON11, MunichJune 13-17, 2011Measurement of Γee · B(ψ ′ hadrons) for ψ ′ – IVKEDR 2011Γee Bhadrons ψ(2S)BES2 2008BES2 2006KEDRBES2 2002Υ rev. 1989MRK I 1975DASP 1979MRK1 19751.822.2S.Eidelman, BINP2.42.6keV1.822.22.42.6Γee (ψ(2S)), keVp.12/21
HADRON11, MunichJune 13-17, 2011Measurement of Γee · B(ψ ′ hadrons) for ψ ′ – VKEDR 2011BES2 2008E835 2007BES2 2006BES2 2002E760 1993200250300350400Γ (ψ(2S)), keVS.Eidelman, BINPp.13/21
HADRON11, MunichJune 13-17, 2011Determination of ψ(3770) Parameters – Iσ, [nb]scan 1scan 2scan 3108VDMq2 aF (q) e 2No 3880σDD̄ Aψ(3770) Aψ′ eiφ B eiφ 2σDD̄ Aψ(3770) Bn.r. F eiφ 2S.Eidelman, BINPp.14/21
HADRON11, MunichJune 13-17, 2011Determination of ψ(3770) Parameters – IIIModel,F(q)M ,[MeV/c2 ]Γ,[MeV]VDM(ψ ′ )3779.7 1.724.9 4.318.5No Interf.3773.2 0.523.9 2.32.53780.5 2.328.2 4.515.3constant3778.1 1.530.4 3.913.711 aq 2 bq 43779.3 1.725.1 4.417.211 aq b3779.0 1.724.4 3.717.71(W Mψ′ )a3780.0 1.925.3 4.717.6VDM (ψ(4039))3778.2 1.630.6 3.912.2C.L. ,[%]2 q2eS.Eidelman, BINPap.15/21
HADRON11, MunichJune 13-17, 2011Determination of ψ(3770) Parameters – IVSourceMass, MeVWidth, MeV 0.3 1.6 5.7 0.5R0 variation0.30.3Event selection0.30.3Luminosity0.10.1Detection efficiency0.10.1Energy assignment0.03–σNR shapeTotal 0.5 1.7KEDR: Mψ(3770) (3779.3 1.7 0.5 1.7 ) MeV,PDG: Mψ(3770) (3772.92 0.35) MeV,S.Eidelman, BINP 5.7 0.7Γψ(3770) (24.9 4.3 5.7 0.7 ) MeVΓψ(3770) (27.3 1.0) MeVp.16/21
HADRON11, MunichJune 13-17, 2011Determination of ψ(3770) Parameters – VA few general conclusions: Mass is higher than in previous measurements, butagrees with BaBar that also took into account interference Width is in reasonable agreement with previous measurements With our data sample we do not observe any shape anomaly Absolutely mandatory to take into account interference: There are usually two solutions with the same mass, width and likelihood,but strongly differing (a factor of up to 3) leptonic width While the current world-average value is Γe e 259 16 eV,with interference effects included it is higher and might be (400-500) eVS.Eidelman, BINPp.17/21
HADRON11, MunichJune 13-17, 2011Search for Narrow Resonances – IKEDR scanned the c.m.energy range from 1.85 to 3.1 GeVsearching for narrow resonancesW (MeV)W (MeV)W (MeV)S.Eidelman, BINPp.18/21
HADRON11, MunichJune 13-17, 2011Search for Narrow Resonances – IIRσE (MeV)Ldt 300 nb 1 was collectedin a scan with a step 2σW (1.4-1.9 MeV)0.70.60.50.41000S.Eidelman, BINP11001200130014001500E (MeV)p.19/21
HADRON11, MunichJune 13-17, 2011Search for Narrow Resonances – III The model: a resonance with MR , ΓRee on top of a flat BG The fits use the range MR 13 MeV MR is varied in 0.1 MeV steps A systematic error of 50% conservatively ΓRee · B(R hadrons) 120 eV,4-5 times more stringent than at ADONE in 1975-1978:γγ2, B B̄ and BOSON groups scanned 1.42-3.1 GeV KEDR hopes to measure R in this W range to 5%S.Eidelman, BINPp.20/21
HADRON11, MunichJune 13-17, 2011Conclusions Masses of J/ψ and ψ(2S) measured. The accuracy reaches (3 5) · 10 6 New precise value of Γe e · B(ψ ′ ) significantly improvesthe values of both leptonic and total width for ψ ′ Interference effects are important for M and Γ of ψ(3770) Multiple solutions make difficult Γe e determination for ψ(3770) No narrow states found between 1.85 GeV and J/ψ New R measurements are planned between 2 and 11 GeVS.Eidelman, BINPp.21/21
Simon Eidelman Budker Institute of Nuclear Physics, Novosibirsk, Russia Outline 1. J/ψand ψ′ masses 2. Parameters of ψ′ 3. Parameters of ψ(3770) 4. Search for narrow resonances 5. Conclusions S.Eidelman, BINP p.1/21
