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

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

BES Detector and the data 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

From “12% rule” to “ρπ puzzle” 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

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*K decays. IHEP Zheng Wang

Theoretical explanations 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

Theoretical explanations 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

PWA of Ψˊ→π+π-π0 ΨˊData Continuum Data Two photons invariant mass 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

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-π0 are very different. IHEP Zheng Wang

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

PWA of Ψˊ→π+π-π0 in Ψˊ→3π process. (770)π, (2150)π are dominant. 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

Summary of the systematic errors on Br(Ψˊ→π+π-π0). VP mode PWA of Ψˊ→π+π-π0 Source Relative error(%) Trigger 0.5 MDC tracking 4.0 Kinematic fit 6.0 Photon efficiency Number of photons 2.0 Background estimation 3.6 Particle ID negligible Total number of Ψˊ Continuum subtraction 3.0 Total 10.5 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

________________________________________________ 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

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

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→K0 K* (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

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

EM Process: 0,,ˊ at Ecm=3650,3686,3773 MeV EM process, hep-ex/0410031 EM Process: 0,,ˊ at Ecm=3650,3686,3773 MeV For EM processes at continuum e+e-  (VP) 0 , , ˊ Pvp(S)=q3vp/3 ; q3vp – momentum of V or P ; Fvp(s) – form factor . For EM processes 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

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

0 form factor BES Preliminary Curve A -- J.Gerard, PLB425(1998)365 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

Results of Ψˊ→VP VP mode BES Preliminary ’ Nevt B(’) (10-5) B(J/) (10-4) PDG04 Q (%)  (770)  5.1  0.7  0.8 127  9 0.40 0.08  (2150)    1.93  0.23 9.2  3.7  ’ 1.05  0.18 17.8  12.9   4.2  0.6 4.5  1.8   <4.3 < 1.6 15.8  1.6 < 0.7  ’ 4.1 2.8 3.1  2.0  0.7 1.67  0.25 26  19   < 3.0 < 0.39 < 0.068   17.8  5.3 3.5  1.0  0.6 6.5  0.7 5.4  1.9  ’ 9.1  3.6 3.3  1.3  0.7 3.3  0.4 9.7  4.5 K+K*-+c.c. 9.6  4.2 2.9  1.3  0.4 50  4 0.58  0.27 K0K*0+c.c. 65.6  9.0 15.0  2.1  1.9 42  4 3.6  0.8 BES Preliminary

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

Summary Thanks ! 谢谢！ Measured BRs or upper limits of VP channels: ˊ (,,)(,,’), K*K (12 channels) In ˊ +π-π0, (770)π decay 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 properties as well as properties of strong interaction. Thanks ! 谢谢！ IHEP Zheng Wang

BESII .VS. CLEO-c Most channels BRs are consistent. BES BR()>CLEO 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

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