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Recent Results from Ψ(2S)  and χ cJ Decays

Recent Results from Ψ(2S)  and χ cJ Decays. 平荣刚 IHEP, Beijing for the BES Collaboration. 中国物理学会 2006 年秋季会议. Data samples. 14M. 2001.Nov.01to 2002.Mar.02. 4M. 3M. 6.42 pb -1 continuum data at Ecm=3.65 GeV for bkg study. Data MC+cont.+Bg. Cont.+Bg. Bg. BESII:Preliminary.

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Recent Results from Ψ(2S)  and χ cJ Decays

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  1. Recent Results from Ψ(2S) and χcJ Decays 平荣刚 IHEP, Beijing for the BES Collaboration 中国物理学会2006年秋季会议 CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  2. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  3. Data samples 14M 2001.Nov.01to 2002.Mar.02 4M 3M 6.42 pb-1 continuum data at Ecm=3.65 GeV for bkg study. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  4. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  5. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  6. Data MC+cont.+Bg. Cont.+Bg. Bg. BESII:Preliminary CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  7. M. Appelquist and H. D. Politzer, PRL34, 43 (1975) This is the famous (or notorious) “12% rule”. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  8. “12% rule”and“ puzzle” • Violation revealed by Mark-II , confirmed by BESI at higher sensitivity. • Extensively studied by BESII • VP mode:  , K*+K-+c.c., K*0K0+c.c., 0,… • PP mode: KSKL, K+K-, +- • VT mode: K*K*2, f2’, a2, f2 • Multi-body: 3(+-), … MARK-II K*K ρπ CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  9. J/, ’ VP BESII : PLB614, 37 (2005); PRD73, 052007 (2006) CLEOc: PRL94, 012005 (2005)

  10. J/, ’  PP: 12% rule BES, PRL 92, 052001 (2004) CLEO, hep-ex/0603020 KK mode enhanced relative to the 12% rule. Pure EM mode  not enhanced, may be suppressed. J/  and ’ are related by ee of charmonia and  form factors. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  11. PRD69(2004)072001 ’ V T † This value from DM2 only Suppressed!! CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang 12 % rule

  12. ’ 3-body PRD71,072006(2005);PRD74, 12004 (2006) 256±18 44.8±8.7 914±42 921±40 CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  13. BESII: PRD71, 072006 (2005) ’ 3-body BESII: PRD74, 12004 (2006) Suppressed!! CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  14. Multi-body ’ decays BESII, PRD73, 052004 (2006) CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  15. Multi-body ’ decays BESII, PRD73, 052004 (2006) Some modes are suppressed, some are enhanced, while some others obey the 12% rule! CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  16. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  17. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  18. Summary: “12%” rule Facts: • ’ VP : suppressed • ’ PP : enhanced/supressed • ’ VT : suppressed • Multi-body : obey/sup • Radiative : enhanced/supressed Seems no obvious rule to categorize the suppressed, the enhanced, and the normal decay modes of J/ and ’. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  19. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  20. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  21. Pair production of vectors c0 c1 c2 Improved precision over PDG (BESI) results on cJKKKK and . First measurement of cJKK. BESII cJ→2(K+K) CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  22. Pair production of vectors 38 c0 28 c2 First observation: B(c0) = (2.290.580.41)10-3 B(c2) = (1.770.470.36)10-3 CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang BES: PLB630, 7 (2005)

  23. cJ BES: PRD73, 052006 (2006)  c0  Evidences for c0 and c0,2. Agree with COM and QCM predictions. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  24. Summary of the test of color octet mechanism ● For χcJ →PP, the theoretical results are in general good agreement with experimental values . ●For χc0 →B Bbar, there is no reliable theoretical interpretation. The experimental values of Br(χcJ →Λ Λbar) decays are quite larger than theo. values. ● More experimental information are desirable for determining the color octec wavefunction of χcJ states. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  25. PWA on cc0!p+p-K+K-. Motivation : ▲Compared withvector and pseudoscalar mesons, little information on scalar and tensor mesons are known. ▲ The decays of ccJ provide a direct window on studing of 0++ and 2++ mesons. • Different way for scalar study: • Start from JPC=0++, 1++, 2++ • Start from gluon+gluon • Pair production of scalars, very different from J/ decays CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  26. c0      K  K  BES: PRD72, 092002 (2005) c0(3414.7±0.6MeV) 1. Qi= 0 ; 2. p()+p( ) > 650 MeV [BG:’   J/ ]; 3. Prob( K K )> Prob(   )& Prob( K K )> Prob( K K K K ); 4. M( )  [497±50] MeV/c2 & second vertex <5mm [BG: KS ]; c1(3511.3±1.3MeV) c2(3556.4±0.9MeV) Event level 5C-fit 1371 events 1.Avoid introducing a huge number of partial waves; 2. constrained by present statistics; our study is devoted to c0     K  K  c0 CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  27. (    )(K  K ) BES: PRD72, 092002 (2005) f0(980) f0(2200) f0(1710) f0(1370) (770) CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang Q. Zhao, PRD72, 074001 (2005), try to understand these data and the scalars …

  28. Without Kappa-kappa S=39. With Kappa-kappa BES: PRD72, 092002 (2005) (K    )(K    ) K*(892)0 K*0/2(1430) K*0(1950) CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  29. BES, c0→+K+K (K  )K BES: PRD72, 092002 (2005) 1371 events K1(1270) K1(1400) K1(1270) M(K) [896±60] MeV K1(1270) 1P1, 3P1 axial-vector-meson mixing: 1P1 : KA=cosθK1(1400)＋sinθK1(1270) 3P1 : KB=cosθK1(1270)＋sinθK1(1400) The mixing angle between K1A and K1B>57 degrees, while in ’ decays to K1K, the angle is <29 degrees (PRL83p1918). Why? M() [700,850] MeV CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  30. Summary PWA of c0      K  K  From the c0      K  K  decay fit results, it is found that scalar resonances have larger decay fractions compared to those of tensors, and such decays provide a relatively clean laboratory to study the properties of scalars, such as f0(980),f0(1370),f0(1710), f0(2200) and so on. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  31. c1 c2 χc1→PPP allowed by spin-parity selection rule Event selection: CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  32. Nsig=418± 60 h Nsig=222±28 (8.8s) Nsig=58± 14 (4.5s) h sideband a0 sideband CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  33. χc1→PT allowed by spin-parity selection rule c0→PPP is suppressed by spin-parity selection; BES: cJ→KK and  CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  34. cc0cc1cc2 PRD74, 12004 (2006) CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  35. Summary Thanks a lot ! CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  36. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  37. CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

  38. 1P1, 3P1 axial-vector-meson mixing: Nonstranger member: strange memeber 1P1 : b1(1235): G=+1 KA=cosθK1(1400)＋sinθK1(1270) 3P1 : a1(1260): G=-1 KB=cosθK1(1270)＋sinθK1(1400) θ ≈45° CPS2006,Sept. 15 - 17, 2006, Beijing Ping Rong-Gang

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