Resonances in Resonances in ΨΨˊ→ˊ→ππ++ππ--ππ00 and stu and study of dy of ΨΨˊ→ˊ→VP VP decays at BESIIdecays 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

Outline

Introduction

IHEP Zheng Wang

• Introduction

• PWA of Ψˊ→π+π-π0

• Study of Ψˊ→VP ((,,)(,,ˊ),K*K )• Summary

BES Detector and the data Introduction

IHEP Zheng Wang

0

2

4

6

8

10

12

14

MKI MKII MKIII CBAL BESI BESII CLEOc

14 Million

Tracking: Main Drift ChamberPhoton ID: BSCHadron ID: MDC(dE/dx)+TOF

6.42pb-1 continuum data (Ecm=3.65GeV) was used to estimate the continuum bg.

From “12% rule” to “ρπ puzzle”

Introduction

IHEP Zheng Wang

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= )ee/J(B)ee)S2((B

)/J())S2((

)ggg/J(B)ggg)S2((B

3s

3s

≈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 }

ρπ Puzzle

Introduction

IHEP Zheng Wang

“12% rule” holds for many exclusive hadronic final state, but violated in Ψ ́→ VP,VT decays compared with the expectation of “12% rule”, the outmost are Ψˊ→ρπ and K*K decays.

Qh values of main J/Ψ and Ψˊhadronic decays in PDG and previous BES results

suppressed

Theoretical explanations

Introduction

IHEP Zheng Wang

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

Theoretical explanations

Introduction

IHEP Zheng Wang

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

PWA of Ψˊ→π+π -π0hep-ex/0408047 submitted to PRL

IHEP Zheng Wang

14M Ψˊdata

2 good track ， 2 more good gamma

One π ID.

electron veto

µ veto

Kinematic fit

J/Ψ→μμ decay veto

Mass of π 0 cut

Samples of Ψˊ→π+π-π0

ΨˊData

Continuum Data

Two photons invariant mass

Continuum contribution are subtracted incoherently in 3 πevents.

PWA of Ψˊ→π+π -π0

hep-ex/0408047 submitted to PRL

IHEP Zheng Wang

Except the suppression in Ψˊdecay, Dalitz plots for J/Ψand Ψˊ +π-π0 are very different.

ρ(770) band

J/Ψ→μμ decay veto

PWA Ψˊ→ π+π -π0

hep-ex/0408047 submitted to PRL

IHEP Zheng Wang

•ML fit for the Dalitz plot.

•Helicity amplitude:

•ρ and its excited states.

•ρ was described by Gounaris-Sakurai(GS) parameter.

Ψˊ π

πρ

π

PWA of Ψˊ→π+π-π0

VP mode

IHEP Zheng Wang

• 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

PWA of Ψˊ→3πVP mode

IHEP Zheng Wang

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.

BE

S P

relimin

ary

Ψˊ→K*(892)K KSK+- +c.c.

hep-ex/0407037 , submitted to PRL

IHEP Zheng Wang

Dalitz plot in ˊK*(892)K KSK

K*

K*0

Ψˊ→K*(892)K

hep-ex/0407037 , submitted to PRL

IHEP Zheng Wang

K* K*09.6±4.2 Evts. 65.6±9.0 Evts.Ψˊ K K* (892)±

Ψˊ→K0 K* (892)0

Br0(15.0±2.1±1.9)10 –5 Br±(2.9±1.3±0.4)10 –5

5.2±2.7 isospin-violation

BE

S P

relimin

ary

Ψˊ→ , 0 ,ˊ,ωη,ωηˊ

IHEP Zheng Wang

VP model

Ψˊ→φη

Ψ→φπ0 not seen

Ψˊ’( ’ +-, +- )

Ψˊ→ωηΨˊ→ωηˊ

(ηˊ→γππ)

Ψˊ→ωηˊ

(ηˊ→ηππ)

EM Process: 0,,ˊ at Ecm=3650,3686,3773 MeV

VP mode, EM process

IHEP Zheng Wang

interference

For EM processes at continuum e+e- (VP) 0 , , ˊ

Pvp(S)=q3vp/3 ; q3

vp – 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 )

BRs (M Ψ(2S) ) & Fvp obtained simultaneously.

EM Process: 0,,ˊ at Ecm=3650,3686,3773 MeV

VP model ,EM process

IHEP Zheng Wang

Ecm=3650 MeV L = 6.42 pb-1 Ecm=3686 MeV N Ψ(2S) = 14M Ecm=3773 MeVL = 17.3 pb-1

ωπ0

ρη

ρηˊ

0 form factor

VP mode ,form factor

IHEP Zheng Wang

Curve A -- J.Gerard, PLB425(1998)365 F(0) ~ 1/s

Curve B –V.Chernyak, hep-ph/9906387 F(0) ~ 1/s2

BE

S P

relimin

ary

Results of Ψˊ→VP

VP model

’ Nevt B(’) (10-5) B(J/) (10-4)

PDG04

Q (%)

(770) 5.1 0.7 0.8 127 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 15.8 1.6 < 0.7

’ 4.1 2.8 4.3 2.9 1.0 1.67 0.25 26 19

< 3.0 < 0.3 < 0.068

17.8 5.3 3.5 1.0 0.6 6.5 0.7 5.4 1.9

’ 9.1 3.6 3.2 1.3 0.6 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

2.111.25.24.19

BES Preliminary

Test of pQCD 12% Rule

IHEP Zheng Wang

PQCD 12% Rule test using BESII Ψˊ→VP results

Summary

IHEP Zheng Wang

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！

BESII .VS. CLEO-cVP mode

Upper limit @90 ％ C.L.

• 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

IHEP Zheng Wang

Br(Ψˊ VP) and FVP(S) for 0,,ˊ

VP mode, EM process

IHEP Zheng Wang

e+e- at Ecm=3650MeV

e+e- ’ at Ecm=3773 MeV

Ψˊ

Ψˊ ’

e+e- at Ecm=3773 MeV

e+e- ’ at Ecm=3650MeV

,ˊ at Ecm=3650,3686,3773 MeV

IHEP Zheng Wang