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 , 2004, Beijing, China

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

3. 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

4. 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

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*K decays.
IHEP Zheng Wang

6. 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

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

8. Continuum contribution are subtracted incoherently in 3 πevents.
hep-ex/ 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-π0 are 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. 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

12. ________________________________________________
VP mode
PWA of Ψˊ→3π
Results on BRs
_____________________________________________________________________________________________________________________
BR BESII (10 – 5 ) PDG04 (10 – 5 )
Ψˊ + -   1.8   5
Ψˊ    0.7  < 8.3
Ψˊ
(2150)   + -   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→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

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

16. EM Process: 0,,ˊ at Ecm=3650,3686,3773 MeV
VP mode, EM process
EM Process: 0,,ˊ at Ecm=3650,3686,3773 MeV
For EM processes at continuum e+e-  (VP) 0 , , ˊ
Pvp(S)=q3vp/ ; 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

17. EM Process: 0,,ˊ at Ecm=3650,3686,3773 MeV
VP model ,EM process
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

18. 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/
F(0) ~ 1/s2
IHEP Zheng Wang

19. Results of Ψˊ→VP VP model BES Preliminary ’ Nevt B(’) (10-5)
B(J/) (10-4)
PDG04
Q (%)
 (770) 
5.1   0.8
 9
0.40 0.08
 (2150) 
 
13.2  4.8
1.78  0.65  0.22
1.93  0.23
9.2  3.7
 ’
2.5  1.7
1.87  1.27  0.36
1.05  0.18
17.8  12.9
 
14.0 4.8
1.88  0.64  0.32
4.2  0.6
4.5  1.8
 
<3.3
< 1.1
 1.6
< 0.7
 ’
4.1 2.8
4.3   1.0
1.67  0.25
26  19
 
< 3.0
< 0.3
<
 
17.8  5.3
3.5   0.6
6.5  0.7
5.4  1.9
 ’
9.1  3.6
3.2   0.6
3.3  0.4
9.7  4.5
K+K*-+c.c.
9.6  4.2
2.9   0.4
50  4
0.58  0.27
K0K*0+c.c.
65.6  9.0
  1.9
42  4
3.6  0.8
BES Preliminary

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

21. 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. (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

22. 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
Upper C.L.
IHEP Zheng Wang

23. 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

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