1 / 26

Qiang Zhao Institute of High Energy Physics, CAS, P.R. China

June 16, 2005. The scalar glueball production in J/  hadronic decays. Qiang Zhao Institute of High Energy Physics, CAS, P.R. China & Department of Physics, University of Surrey, Guildford, U.K. Place for “Glueball” in the meson spectroscopy

rollo
Télécharger la présentation

Qiang Zhao Institute of High Energy Physics, CAS, P.R. China

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. June 16, 2005 The scalar glueball production in J/ hadronic decays Qiang Zhao Institute of High Energy Physics, CAS, P.R. China & Department of Physics, University of Surrey, Guildford, U.K. Place for “Glueball” in the meson spectroscopy “Puzzles” from the recent BES data for scalar mesons Glueball and QQ* mixings in the scalar mesons Mechanisms for scalar meson production in J/V f0  V PP ( V= , ; P = , , , K) Summary In collaboration with Frank Close (Oxford)

  2. Meson spectroscopy I) QQ* mesons Quarks as building blocks of hadrons: meson (qq*), baryon (qqq) Convention (Particle Data Group): 1) Quark has spin 1/2 and baryon number 1/3; 2) Quark has positive parity and antiquark has negative parity; 3) The flavor of a quark has the same sign as its charge.

  3. QQ* mesons: • Mesons are bound state of QQ* with baryon number B=0; • The parity is given by P=(1)L+1with orbital angular momentum L; • The meson spin J is given by |LS| < J < | L+S| , where S=0, 1 are • the total spin of the quarks. • 4. Charge conjugate is defined as C=(1)L+S for mesons made of quark • and its own antiquark. For light quarks: u, d, and s, the SU(3) flavor symmetry constrains the number of flavor QQ* multiplet: 3  3* = 8  1 3 4 1 1

  4. II) Non-QQ* mesons Type (a): JPC are not allowed by QQ* configuration For states in natural spin-parity series P=(1)L+1 =(1)J , the state must have S=1 and hence CP=(1)(L+S)+(L+1) =+1. Therefore, mesons with natural spin-parity but CP= 1 will be forbidden, e.g. 0+, 1+, 2+, 3+, … L + Natural: 0++, 1, 2++, 3, … Unnatural: ( 0), 1++, 2,3++, …  S=1 L + Unnatural: 0+, 1+, 2+, 3+, …  S=0

  5. Type (b): Mesons have the same JPC as a QQ*, but cannot be accommodated into the SU(3) nonet: 3  3* = 8  1 3 4 1 1 Mass f0(1710) Glueball ? QQ*-glue mixing ? f0(1500) f0(1370) (1020) (958) f0(980) Multiquarks ? (782) /f0(600) (547) 0 1 0 I=0

  6. Glueball: Mesons are made of colored gluons confined by strong interaction  g M J/ g R=G f0 Lattice 0++: 1.5 ~ 1.7 GeV Exp. Scalars: f0(1370) f0(1500) f0(1710) f0(1790) (?) Lattic QCD prediction Morningstar and Peardon, PRD60, 034509 (1999)

  7. “Puzzles” in the recent experimental data for scalar mesons • Beijing Spectrometer (BES) • e+ e-  J/  V f0  V PP, • V=, ; PP=, , , KK* • WA102 at CERN • p p  p p f0  pp PP

  8. f0(1370) at BES • f0(1370)clearly seen in J/  , but not seen in J/  . f0(1370) NO f0(1370) S. Jin, Plenary talk at ICHEP04

  9. f0(1710) at BES • Clear f0(1710) peak in J/  KK. • Nof0(1710) observed in J/   ! f0(1710) NO f0(1710) S. Jin, Plenary talk at ICHEP04

  10. Unusual beahvior of f0(1370), f0(1500) and f0(1710) prod. BES exp. for J/V f0VPP : i) f0(1370) has been seen clearly in J/ f0(1370), but not in J/; stronger f0(1370) coupling? ii) f0(1500) have not been directly see in J/KK*, , KK*, ; Why suppressed here? iii) f0(1710) is observed clearly in J/KK* and KK*, but not in , . Also, br(J/ KK*) ~6 br(J/KK*). stronger f0(1710) coupling? WA102 exp. for p p  pf ( f0) ps; f0  PP: i) f0(1370)  is dominant over KK*, , ; nonstrange nn* ii) f0(1500) was seen in all channels, and dominated by ; mixture of nn*, ss*, and gg ? iii) f0(1710) KK* is dominant. ss*

  11. Glueball and QQ* mixing in the scalar mesons In the basis of |G> = gg, |S> = ss*, and |N> = nn* = (uu*+dd*)/2, the glueball-quarkonia mixing can be expressed as: S G N The f0 states: Close, et al., PLB353, 385(1995); PRD53, 295(1996); PLB483, 345(2000).

  12. Parameterization of f0  PP r3 g0 r2 g0 g0 P   f0 P Partial decay widths for f0  PP: Close and Zhao, PRD71, 094022(2005)

  13. Experimental data from WA102 Unitarity constraints:

  14. f0 states 1710 S 1500 G 1370 N Lattice QCD: MG ~ 1.5 – 1.7 GeV - flavour mixing: = 8 cos - 1 sin = |S> - |N> = 8 sin + 1 cos = |S> + |N>

  15. f0 mixing matrix determined in f0  PP gg ss* nn*  KK* Satisfies: i) f0(1370)  is dominant over KK*, , ; nonstrange nn* ii) f0(1500) was seen in all channels, and dominated by ; mixture of nn*, ss*, and gg iii) f0(1710) KK* is dominant. ss*

  16. Scalar mesons production in J/  V f0 II) Doubly disconnected diagram I) Singly disconnected diagram  (ss*) g  (ss*) c c g J/ J/ f0 (ss*) c* f0 (nn*) c* III) Glue configuration pQCD Okubo-Zweig-Iizuka (OZI) rule: I) ~III) ~   II) =g2/4 ~ 0.3 However …  (ss*) c J/ f0 (gg) c*

  17. Implications of the OZI rule: gg ss* nn*  KK* i) OZI rule on f0(1370): br(J/ f0(1370)KK*)<< br(J/ f0(1370)) Exp: br(J/ f0(1370)) is dominant ! ii) OZI rule on f0(1710): br(J/ f0(1710)KK*) > br(J/ f0(1710)KK*) Exp: br(J/ f0(1710)KK*) / br(J/ f0(1710)KK*) ~ 0.3 !

  18. Factorization of J/  V f0  V P P V (, ) Transition amplitudes via potential V J/ P f0 III) I) II) P OZI-suppressed Doubly disconnected Project to the final physical states: Gluon-counting rule: I) ~ III)

  19. I) Singly disconnected diagram II) Doubly disconnected diagram (ss*), (nn*) • (ss*), (nn*) g c c g J/ J/ f0(ss*), (nn*) c* f0(nn*), (ss*) c* III) Glue configuration Gluon-counting rule: I) ~ III) (ss*) (nn*) c J/ f0(gg) c*

  20. Partial decay width for J/  V f0  V P P (nn*) (ss*) c c J/ J/ G(gg) G(gg) c* c* Flavor-blindness of quark-gluon interaction:

  21. Step 1: Direct test of the OZI rule BES Experiment: br(J/ f0(1710)KK*) = (2.0  0.7)  104 br(J/ f0(1710)KK*) = (13.2  2.6)  104 a) OZI rule applies: r  0 PDG estimate: Rexp = 0.75 b) OZI rule violated: r ~ 1 where r = 2.2

  22. Step 2: Normalize the G production Normalized glueball production br. ratios Scalar decay br. ratios

  23. Step 3: Theoretical predictions for J/V f0  V KK*, V  The “puzzle” can be naturally accounted for in the glueball-QQ* mixing scheme. Puzzle  Evidence for scalar glueball-QQ* mixings

  24. Further test of the gluon-QQ*mixings 1 billion J/ events from BES gg ss* nn* • f0    • probe the quark components of the scalars: • f0(1370) : f0(1500) : f0(1710) ~ 12 : 2 : 1 • ii) J/   f0 • f0(1710) > f0(1500) > f0(1370) • iii) f0   V, (V= , 0) • f0(1710)  ( ) > ( 0) • f0(1370)  ( ) < ( 0) • f0(1500)  ( ) < ( 0) • iv) Constrain the doubly OZI violation processes gg ss* nn*

  25. Summary I. The glueball contents are essentially important for interpreting the “puzzling” data from BES for the scalar meson production in J/ decays. II. The strong glueball-QQ* mixing implies the failure of the OZI rule in J/  V f0, and suggests the crucial role played by the doubly disconnected processes. III. A normalization of the glueball production rate is obtained, which possesses predictive power for the study of the glueball mixing effects in the J/ radiative decay channels. Further experimental data from BES, CLEO-c, GSI (?) will be useful for establishing these f0 states as glueball-QQ* mixing states.

  26. Thanks !

More Related