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Resonances in Ψˊ Decays at BESII: Study of Ψˊ→ VP and Ψˊ→ π+π-π0 Processes

This topical seminar covered the study of resonances in Ψˊ decays at the BESII facility in China, focusing on the processes Ψˊ→ VP and Ψˊ→ π+π-π0. The presentation included an introduction, outline, partial wave analysis of the decays, and discussion of theoretical explanations related to the observed phenomena. Experimental data and results from various decay modes were presented, shedding light on the intricate dynamics of these processes.

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Resonances in Ψˊ Decays at BESII: Study of Ψˊ→ VP and Ψˊ→ π+π-π0 Processes

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  1. Resonances in Ψˊ→π+π-π0 and study of Ψˊ→VP decays at BESII Zheng Wang IHEP, Beijing,10039 China For BES Collaboration. Topical Seminar on Frontier of Particle physics 2004: QCD and Light Hadrons Sep. 26-30, 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 track，2 more good gamma One π ID. electron veto µ veto Continuum Data Kinematic fit J/Ψ→μμ decay veto Two photons invariant mass Mass of π0 cut Continuum contribution are subtracted incoherently in 3 πevents. 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→3π 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

  13. 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

  14. 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

  15. VP model Ψˊ→ , 0 ,ˊ,ωη,ωηˊ Ψˊ→φη Ψ→φπ0 not seen Ψˊ’ ( ’+-, +- ) Ψˊ→ωηˊ (ηˊ→γππ) Ψˊ→ωηˊ (ηˊ→ηππ) Ψˊ→ωη IHEP Zheng Wang

  16. VP mode, EM process 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

  17. VP model,EM process 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

  18. 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

  19. VP model Results of Ψˊ→VP BES Preliminary

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

  21. 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. (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

  22. 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 Upper limit @90％ C.L. IHEP Zheng Wang

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

  24. ,ˊ at Ecm=3650,3686,3773 MeV e+e-  at Ecm=3650MeV Ψˊ e+e-  at Ecm=3773 MeV e+e- ’ at Ecm=3650MeV e+e- ’ at Ecm=3773 MeV Ψˊ’ IHEP Zheng Wang

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