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Collaboration on J/  physics analyses

Collaboration on J/  physics analyses. Xiaoyan SHEN (for J/  group) Institute of High Energy Physics, CAS June 17, 2004, IHEP, Beijing Review meeting for Sino-Japan program. The Beijing Electron Positron Collider. L ~ ~5 10 30 /cm 2 s at J/ peak E cm ~ 2-5 GeV.

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Collaboration on J/  physics analyses

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  1. Collaboration on J/ physics analyses Xiaoyan SHEN (for J/ group) Institute of High Energy Physics, CAS June 17, 2004, IHEP, Beijing Review meeting for Sino-Japan program

  2. The Beijing Electron Positron Collider L ~ ~51030 /cm2s at J/ peak Ecm~2-5 GeV An unique e+e- machine in the world in the -charm energy region since 1989. (CESRc is operating now!)

  3. BESII Detector VC: xy = 100 m TOF: T = 180 ps  counter: r= 3 cm MDC: xy = 220 m BSC: E/E= 22 % z = 5.5 cm dE/dx= 8.5 %  = 7.9 mr B field: 0.4 T p/p=1.7(1+p2) z = 2.3 cm

  4. J/ data samples CBAL 2.2M J/ events DM2 8.6M J/ events BESII 58MJ/ events MKIII 5.6M J/ events BESI 7.8M J/ events MKII 5.6M J/ events

  5. Main topics with BESII 58M J/ data • search for non- states • study of the hadron spectroscopy • search for more J/ decay channels • probing for new physics in J/ decays • c decays

  6. The BES Collaboration Korea (4) Korea University Seoul National University Chonbuk National University Gyeongsang Nat. Univ. USA (4) University of Hawaii University of Texas at Dallas Colorado State University Stanford Linear Accelerator Center UK (1) Queen Mary University China (18) IHEP of CAS Univ. of Sci. and Tech. of China Shandong Univ., Zhejiang Univ. Huazhong Normal Univ. Shanghai Jiaotong Univ. Peking Univ., CCAST Wuhan Univ., Nankai Univ. Henan Normal Univ. Hunan Univ., Liaoning Univ. Tsinghua Univ., Sichuan Univ. Guangxi Univ., Guangxi Normal Univ. Jiangsu Normal Univ. Japan (5) Nihon University Tokyo Institute of Technology Miyazaki University KEK U. Tokyo

  7. Japanese  group: T. Tsuru, K. Takamatsu, and K. Ukai KEK, High Energy Accelerator Research Organization, Japan T. Komada, K. Yamada and S. Ishida Nihon University, Tokyo 101-8308, Japan M. Ishida Meisei University, Tokyo 191-8506, Japan T. Matsuda Miyazaki University, Miyazaki 889-2192, Japan I. Yamauch Tokyo National College of Technology, Tokyo 193-0942, Japan BES J/ group

  8. 1. study of  • Better experimental knowledge on the 0++ low energy hadron spectrum is important to the understanding of QCD in non-perturbative region. • The determination of  is helpful in understanding how QCD realizes chiral symmetry.

  9.  observed as  S-wave in  scattering • data. • phase shift analysis on CERN-Munich data : • I=0  S-wave phase shift is only 90o. • most analyses against the existence of . •  had been disappeared since PDG76.

  10. low mass enhancement in DM2 and BESI data on • J/   • huge event concentration in the I=0 S-wave  • channel at M  500 – 600 MeV in pp central • production experiment • re-analysis of - phase shift by S. Ishida => 180o. •  resonance is unavoidable in chiral perturbative • theory. • Chiral symmetry gives: (47030) –i (295  20) MeV • E791 data (2001) on D+  +-+

  11. The  pole in BESII M(+-0) M() M(+-)

  12. Fit to J/→+ (whole mass region) b1(1235) Channels fitted to the data: J/f2(1270)  f0(980) b1(1235) ’(1450) f2(1565) f2(2240) preliminary f0 contribution f2 contribution

  13. Fit to J/→+ (M < 1.5 GeV) Channels fitted to the data: J/f2(1270)  f0(980) b1(1235) phase space

  14. Fit results: Averaged pole position: MeV submitted to P. L. B (hep-ex/0406038)

  15. 2. study of  • early K scattering data didn’t show  pole. • re-analysis of K elastic scattering by S. Ishida showed the existence of . • Further study based on chiral perturbation theory gave  pole as: (770 – i 341 )MeV or (754  22) – i (23027 ) MeV • a nonet made up of , , f0(980) and a0(980)

  16. E791 data on D+K-++ shows a scalar K • resonance with: • CLEO D0 K-+0 (lower stat.) finds no . • FOCUS data on K+  K-++ require K*0 • interference with either a constant amplitude • or a broad spin 0 resonance in K. • BESI data on J/K*K shows .

  17. Study of  from BESII J/ K*K and K+K-+- Before K*(892) 0 cut M(K) After K*(892) 0 cut M(K)

  18. Study of  from J/ K*K PWA  contribution

  19. Study of  from J/ K*K PWA

  20. Study of  from J/ K+K-+- PWA Pole position: (7602040) – i(4204560) MeV

  21.  results were reported at: • ICHEP’02, 2002, Netherland • International Symposium on Hadron Spectroscopy, Chiral Symmetry and Relativistic Description of Bound Systems, Feb. 24 – 26, 2003, Tokyo, Japan • International workshop on Hadron Spectroscopy and Search for Chiral Particles in J/ decay data at BES, Feb. 28 – March 1, 2003, KEK, Japan • Hadron’03, 2003, Germany

  22. 3. CP test in J/ decays --- CP violation was first discovered in K system --- CP violation was also found in B system --- no experimental indication of CP violation in other processes --- search for CP violation in other places where SM predicts no or tiny CP violation J/   for CP test Analyzed by Masakazu Kurata, from Univ. of Tokyo

  23. Activities • In Oct. of 2000, K. Takamatsu, S. Ishida, M. Ishida and T. Tsuru visited IHEP. A workshop was held to discuss the possibility of searching for ， and other chiral particles with BESII J/ data. • In June of 2001, K. Takamatsu attended BES annual meeting.  and  analyses were discussed. • Collaboration started and BES J/  +- and J/  K*K data were sent to Japanese  group for the study of  and .

  24. In March of 2002, K. Takamatsu and M. Ishida visited • IHEP. A workshop was held for  and  studies. • In June of 2002, T. Tsuru and T. komada attended • BES annual meeting. Both Japanese  group and • BES J/ group reported  results, based on BESII • J/ data. A special discussion meeting for  was held. • Wu Ning, from BES, visited KEK and Nihon Univ. • for  and  analyses (one month). • In Feb. of 2003, 4 people from BES attended the • international symposium in Japan.

  25. In March of 2003, K. Takamatsu and K. Ukai visited • IHEP. • In March of 2004, K. Takamatsu, T, Tsuru, K. Ukai and T. Komada visited IHEP. Worked with Wu Ning and internal referees. • In May of 2004, Wu Ning visited KEK (one week). • In the May of 2004, K. Takamatsu and T. Komada attended BES annual meeting. The publication issue was discussed. • Masakazu Kurata, from Univ. of Tokyo, will stay at IHEP for 1.5 month for the analysis of J/  .

  26. Future plan • Get the  results published • Finish the work on searching for CP violation in J/  . Publish the results. • Search for more chiral particles with BES data.

  27. Thank you! 谢谢！

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