1 / 32

NEW EXOTIC RESONANCES

NEW EXOTIC RESONANCES. Eberhard Klempt HISKP Universität Bonn. 1. The search for pentaquarks 2. New quarkonium resonances. DESY Theory workshop Quantum Chromodynamics: From the MeV to the TeV Scale

chi
Download Presentation

NEW EXOTIC RESONANCES

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. NEW EXOTIC RESONANCES Eberhard Klempt HISKP Universität Bonn 1. The search for pentaquarks 2. New quarkonium resonances DESY Theory workshop Quantum Chromodynamics: From the MeV to the TeV Scale September 27th – 30th, 2005

  2. The search for pentaquarks

  3. Pentaquarksin quark models PRL 91 (2003) 232003 PL B 586 (2004) 303 predicted PL B 570 (2003) 185

  4. LEPS COSY-TOF pp  S+Q+. The initial evidence for Pentaquarks DIANA CLAS-D SAPHIR CLAS-p Neutrino NA49 HERMES 6.7 1862MeV ZEUS SVD

  5. The Q+ width • Measured width dominated by • experimental resolution • Analysis of K+A data give limit of few MeV. Current best value K+D -> X K+D X GQ = 0.9 +/-0.3 MeV • Very narrow for a hadronically • decaying particle with mass ~100 MeV • above threshold: • Q+(1540) -> nK+, pK0 W. Gibbs, Phys.Rev.C70, 054208 (2004) Belle: G < 0.64 MeV (90% CL) @ M = 1.539 GeV

  6. Q+ searches in hadronisation experiments DELPHI CDF K-p Min.bias events Jet events L(1520) K0sp

  7. Non-observation of Q+ Group Reaction Limit BES e+e--> J/Y ->QQ < 1.1 x 10-5 B.R. Belle e+e- -> B0B0 -> ppK0X < 2.3 x 10-7 B.R. BaBar e+e--> U(4s) -> pK0X < 1.0 x 10-4 B.R. HERA-B pA -> K0pX Q/L* < 0.02 CDF pp -> K0pX Q/L* < 0.03 PHENIX Au + Au –> K- nX not given SPHINX pC -> Q+K0X Q+K0/L*K+< 0.02 HyperCP pA -> Q+K0X Q+/pK0 < 0.002 + further results

  8. High Statistics CLAS(d) result Model-independent uppper limit 95% CL for Q+ is < 20nb. With assumptions about the spectator, we can set a model dependent upper limit to the cross section of <4-5 nb. Supersedes CLAS (and LEPS) data preliminary M(nK+)(GeV)

  9. n g Q+ K+ p+ p K0 p− Search for the Q+ (1540) on proton target • TheK0is detected via itsKScomponent decaying intop+p- • Final state neutron is identified using the missing mass technique • Strangeness is tagged detecting theK+ • Using the full statistics (70 pb-1) a total of ~120000 events are selected Supersedes Saphir data

  10. HERMES (e+dKS0p + X) ZEUS (e-pe-KS0p + X) *(1480) M=15223 MeV ~5 M=15283 MeV ~5 Preliminary 233 fb-1 e+ e- data e-Be electroproduction at Babar Possible acceptance loss in low mass region: (PID requires p(p) >4.1 GeV/c; p(KS0)>3 GeV/c) Fit uses *(1480) [PDG 1star]

  11. COSY-TOF L(1520) p pp  S+Q+. n n K+ Do pentaquarks exist ? A few niches need to be clarified before this chapter can be closed • Original claims for pentaquarks false gp > K- p+ nK+ LEPS: g d fL(1520) Q+ Excesses are seen at 1.53 GeV and at 1.6 GeV above the background level. Q+ detected in missingmass

  12. New resonances h`c(3638) c c hc´ h1c X(3872) X(3940) Y(3940) Z(3930) X(4260) c d D Ds

  13. CLEO Collaboration, arXiv:hep-ex/0508037. h1c(3524) h1c Select Eg range plot p0 recoil mass

  14. h1c(3524) CLEO Collaboration, arXiv:hep-ex/0508037

  15. h1c(3524)

  16. h1c(3524) M =[3523.6 +/- 0.9 (stat) +/- 0.5 (sys)] MeV/c2 d = [1.8 +/- 0.9 (stat) +/- 0.5 (sys)] MeV/c2. cog = [5.(2++)+3.(1++)+1.(0++)]/9 dcog = 0 confinement potential is scalar

  17. hc(2S)(3638) h´c(3638) 2g Mass splittings compatible with potential models Belle Babar

  18. B+->K+- (p+p- J/y)decays X(3872) S.K. Choi et al., Phys. Rev. Lett. 91, 262001 (2003) S.K. Choi et al., Phys. Rev. Lett. 89, 102001 (2002) [Erratum-ibid. 89, 129901 (2002)] D. Acosta et al., Phys. Rev. Lett. 93, 072001 (2004) V.~M.~Abazov et al., Phys. Rev. Lett. 93, 162002 (2004) B.~Aubert et al., Phys. Rev. D 71, 071103 (2005) D. M. Asner et al., Phys. Rev. Lett. 92, 142001 (2004) B. Aubert et al, Phys. Rev. Lett. 92, 142002 (2004)

  19. X(3872) K.Abe et al., hep-ex/0505037 w K. Abe et al., PRL 94(2005)182002 K.Abe et al., hep-ex/0505037 Ratio J/r to J/w 1+-0.4+-0.3 Large isospin violation

  20. X(3872) Belle: B > K (D0D0p0) Thresholds: D0D 0p0 3864.2 D0D 0* 3871.3

  21. X(3872) BELLE X(3872)

  22. X(3872) X,Y,Z cc1(2P) (model) Thresholds: J/y w : +7 MeV J/y r : -5 MeV D+D *- : +7 MeV D0D0* : -1 MeV 3872 X(3872) > g J/y X(3872) > pp J/y Expected 300 times larger = 0.14 X(3872)DoDo* molecule (S-wave, pexchange) Swanson. PLB588 (2004) 189 Tornqvist, PLB590 (2004) 209 Swanson. PLB598 (2004) 197 Kalashnikova, PRD 72 (2005) 034010

  23. Z(3930) BELLE

  24. Z(3930)

  25. Z(3930) Z(3930) radial excitation of c2(3556)

  26. X(3940) Double charm production: e+e- to J/y + cc P.~Pakhlov [Belle Collaboration], arXiv:hep-ex/0412041. X(3940) = Z(3940)? Decay modes incompatible!X(3980) = hc (3S) ?Maiani: four--quark state !

  27. Y(3940) B+ to K+ wJ/y K. Abe et al., PRL 94 (2005) 221805 Y(3940) = Z(3940)? Decay modes incompatible! Y(3940) = hybrid ? X, Y, Z three resonances ? Hard to believe !

  28. X(4260)

  29. Summary • Pentaquarks are deadly sick, recovery unlikely. • High energy experiments are blooming! • Spectrum of cc bound states completed. • New cc states discovered,cc above DD threshold: quarkonia hybrids tetraquarks molecules

More Related