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Measurements of Ψˊ→ VP decays at BESII

Measurements of Ψˊ→ VP decays at BESII. Zheng Wang CCAST, Beijing,10039 China For BES Collaboration. The 3rd international Quarkonium Working Group (QWG) workshop Oct. 12-15, 2004, Beijing, China. Introduction. Outline. Introduction PWA of Ψˊ→ π + π - π 0 Study of Ψˊ→ VP

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Measurements of Ψˊ→ VP decays at BESII

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  1. Measurements of Ψˊ→VPdecays at BESII Zheng Wang CCAST, Beijing,10039 China For BES Collaboration. The 3rd international Quarkonium Working Group (QWG) workshop Oct. 12-15, 2004, Beijing, China

  2. Introduction Outline • Introduction • PWA of Ψˊ→π+π-π0 • Study of Ψˊ→VP • ((,,)(,,ˊ),K*K ) • Summary IHEP Zheng Wang

  3. Introduction BES Detector and the data 14 Million Tracking: Main Drift Chamber Photon ID: BSC 6.42pb-1 continuum data (Ecm=3.65GeV) was used to estimate the continuum bg. Hadron ID: MDC(dE/dx)+TOF IHEP Zheng Wang

  4. Introduction From “12% rule” to “ρπ puzzle” J/ and ’ hadronic decays proceed via 3 gluons or a virtual photon, neglect the difference of S at J/ and ’ , the ratio of ’ and J/ BRs is : Qh= ≈12% • Suppression in VP mode ( & K*K ) revealed by MARK-II • { M.E.B. Franklin et al, PRL 51 (1983) 963 } • Suppression confirmed by BESI with higher sensetivity • { Y.S.Zhu, Proc. of ichep ‘96, p.507 } IHEP Zheng Wang

  5. Introduction ρπ Puzzle suppressed Qh values of main J/Ψ and Ψˊhadronic decays in PDG and previous BES results “12% rule” holds for many exclusive hadronic final state, but violated in Ψˊ→VP,VT decays compared with the expectation of “12% rule”, the outmost are Ψˊ→ρπ and K*Kdecays. IHEP Zheng Wang

  6. Introduction Theoretical explanations Brodsky, Lepage, Tuan:{ PRL 59 (1987) 621 } Intermediate vector glueball Chaichian & Torngvist :{ NP B323 (1989) 75 } Hadronic form factor Pinsky :{ PL B236 (1990) 479 } Generalized hindered M1 transition Li-Bugg-Zou{ PR D55 (1997) 1421 } Final-state interaction Brodsky-Karliner{ PRL 78 (1997) 4682 } Intrinsic charm |qqcc> Fock components of the light vector mesons Chen-Braaten { PRL 80 (1998) 5060 } Fock state with cc pair in a color-octet IHEP Zheng Wang

  7. Introduction Theoretical explanations Gerard-Weyers { PL B462 (1999) 324 } cc annihilation into 5g via 2 steps Feldmann-Kroll { PR D62 (2000) 074006 } Decays thru light-quark Fock component by a soft mechanism Suzuki { PR D63 (2001) 054021 } (2S) - vector glueball mixing Rosner { PR D64 (2001) 094002 } (2S) - (1D) mixing J. P. Ma { PR D65 (2002) 097506 } Relativistic Correction IHEP Zheng Wang

  8. hep-ex/0408047 submitted to PRL PWA of Ψˊ→π+π-π0 14M Ψˊdata ΨˊData 2 good tracks，2 good photons One π ID. electron veto(dE/dx & BSC) µ veto Continuum Data Kinematic fit (Prob(4C)>0.01) J/Ψ→μμ decay veto(Mπ+π-<2.95GeV Two photons invariant mass Mass of π0 cut Continuum contributions are subtracted incoherently in 3πevents. Samples of Ψˊ→π+π-π0 IHEP Zheng Wang

  9. hep-ex/0408047 submitted to PRL PWA of Ψˊ→π+π-π0 ρ(770) band J/Ψ→μμ decay veto Except the suppression in Ψˊdecay, Dalitz plots for J/Ψand Ψˊ+π-π0are very different. IHEP Zheng Wang

  10. hep-ex/0408047 submitted to PRL PWA Ψˊ→π+π-π0 • ML fit for the Dalitz plot. • Helicity amplitude: • ρ and its excited states. • ρ was described by Gounaris-Sakurai(GS) parameter. Ψˊ π ρ π π IHEP Zheng Wang

  11. VP mode PWA of Ψˊ→π+π-π0 • Ψˊ→ρ(770)π decay mode is observed for the first time. • in Ψˊ→3π process. (770)π, (2150)π are dominant. • 3π: (770)π: (2150) π • = 1:0.28±0.03:1.07±0.09 IHEP Zheng Wang

  12. VP mode PWA of Ψˊ→π+π-π0 Summary of the systematic errors on Br(Ψˊ→π+π-π0). For the ρ(770)π and ρ(2150)π the uncertainties of fitting with different high mass ρ sates and different background shapes are also included. (16.0% & ) IHEP Zheng Wang

  13. VP mode PWA of Ψˊ→π+π-π0 Results on BRs _____________________________________________________________________________________________________________________ BR BESII (10 – 5 ) PDG04 (10 – 5 ) Ψˊ+ -0 18.1  1.8  1.9 8  5 Ψˊ5.1  0.7  0.8 < 8.3 Ψˊ (2150) + -0 19.4  2.5 ________________________________________________ • 1st measurement or precision much improved. • Interference between ρand its excited states was taken into account. BES Preliminary IHEP Zheng Wang

  14. hep-ex/0407037 , submitted to PRL Ψˊ→K*(892)K KSK+- +c.c. K* K*0 Dalitz plot in  ˊK*(892)K  KSK IHEP Zheng Wang

  15. hep-ex/0407037 , submitted to PRL Ψˊ→K*(892)K K* 9.6±4.2 Evts. K*0 65.6±9.0 Evts. BES Preliminary ΨˊK K* (892)± Ψˊ→K0K* (892)0 Br±(2.9±1.3±0.4)10 –5 Br0(15.0±2.1±1.9)10 –5 5.2±2.7 isospin-violation IHEP Zheng Wang

  16. VP mode , hep-ex/0408118 Ψˊ→ , 0 ,ˊ,ωη,ωηˊ Ψˊ→φη Ψˊ→φπ0 not seen Ψˊ’ ( ’+-, +- ) Ψˊ→ωηˊ (ηˊ→γππ) Ψˊ→ωηˊ (ηˊ→ηππ) Ψˊ→ωη IHEP Zheng Wang

  17. EM process, hep-ex/0410031 EM Process: 0,,ˊ at Ecm=3650,3686,3773 MeV ForEMprocesses at continuum e+e- (VP) 0 , , ˊ Pvp(S)=q3vp/3 ; q3vp – momentum of V or P ; Fvp(s) – form factor . ForEMprocesses at Ψˊ (VP) 0, , ’ =R+cont(INT  0, P.Wang et al, PL B593 (2004) 89 ) interference BRs (M Ψ(2S)) & Fvp obtained simultaneously. IHEP Zheng Wang

  18. EM process, hep-ex/0410031 EM Process: 0, , ˊ at Ecm=3650, 3686, 3773 MeV ωπ0 ρη ρηˊ Ecm=3650 MeVL = 6.42 pb-1 Ecm=3686 MeV N Ψ(2S) = 14M Ecm=3773 MeVL = 17.3 pb-1 IHEP Zheng Wang

  19. VP mode, form factor 0 form factor BES Preliminary Curve A -- J.Gerard, PLB425(1998)365 F(0) ~ 1/s Curve B –V.Chernyak, hep-ph/9906387 F(0) ~ 1/s2 IHEP Zheng Wang

  20. VP mode Results of Ψˊ→VP BES Preliminary

  21. Test of pQCD 12% Rule 12% Rule PQCD 12% Rule test using BESII Ψˊ→VP results IHEP Zheng Wang

  22. Summary Measured BRs or upper limits of VP channels: ˊ(,,)(,,’), K*K (12 channels) In ˊ +π-π0,(770)πdecay was observed for the first time. Br(Ψˊ)= (5.1  0.7  0.8)Χ10-5. (770) & (2150)dominant. Observe large isospin-violation in ˊ K*K channel. F(0,,ˊ) at Ecm=3650, 3686, 3773 MeV measured. Tested 12% rule for all these decay modes. Some suppressed, some consistent. 12% rule seems to be too simplistic. A theory which can quantitatively describe these data is desired. More and accurate J/ ,ˊ and continuum data are helpful to elucidate the J/ and ˊ propertiesas well as properties of strong interaction. Thanks ! 谢谢！ IHEP Zheng Wang

  23. VP mode BESII .VS. CLEO-c • Most channels BRs are consistent. • BES BR()>CLEO • by ~ 3 because the different treatment of continuum BG. and the interference between ρ(770) and its excited state in PWA. • BR(K*0K0) are deviated (different treatment of the continuum contribution) Upper limit @90％ C.L. IHEP Zheng Wang

  24. VP mode, EM process Br(ΨˊVP) and FVP(S) for 0,,ˊ IHEP Zheng Wang

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