• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to previous page

Study of Direct CP Violation

Research Project

Project/Area Number 09246104
Research Category

Grant-in-Aid for Scientific Research on Priority Areas (A)

Allocation TypeSingle-year Grants
Research InstitutionNagoya University

Principal Investigator

OHSHIMA Takayoshi  Nagoya University, Department of Physics Professor, 大学院・理学研究科, 教授 (00134651)

Co-Investigator(Kenkyū-buntansha) TAKAHASHI Tamotsu  Osaka-city Univ. Dep. of Physics, Prof., 理学部, 教授 (20047137)
NOGUCHI Seishi  Nara Women Univ. Dep. of Physics, Prof., 理学部, 教授 (90093559)
SUZUKI Shiro  Nagoya Univ. Dep. of Physics Ass. Prof., 大学院・理学研究科, 助教授 (50089851)
NITOH Osamu  Tokyo Univ. of Agriculture and Technology, Dep. Of Applied Physics, Ass. Prof., 工学部, 助教授 (00189333)
SUMIYOSHI Takayuki  High Energy Accelerator Reserch Organization, Institute of Particle and Nuclear Studies, Ass. Prof., 素粒子原子核研究所, 助教授 (30154628)
杉山 晃  名古屋大学, 大学院・理学研究科, 助手 (80187674)
宮林 謙吉  奈良女子大学, 理学部, 助手 (40273833)
Project Period (FY) 1997 – 2000
Project Status Completed (Fiscal Year 2001)
Budget Amount *help
¥201,000,000 (Direct Cost: ¥201,000,000)
Fiscal Year 2000: ¥32,600,000 (Direct Cost: ¥32,600,000)
Fiscal Year 1999: ¥59,500,000 (Direct Cost: ¥59,500,000)
Fiscal Year 1998: ¥57,000,000 (Direct Cost: ¥57,000,000)
Fiscal Year 1997: ¥51,900,000 (Direct Cost: ¥51,900,000)
KeywordsDirect CP Violation / Kobayashi-Maskaa Matrix / φ_3 CP-Angle / T-lepton's CP Vidaton / Partide Identification / Cherenkov Radiation / レプトンセクターでのCP / T / 時間分解能 / B中間子 / CP対称性 / CKMマトリックス / タウ・レプトン / T不変性 / TOP検出器 / 粒子識別チュレンコフ装置 / CKM マトリックス / タウレプトン / 粒子識別装置 / CP非保存 / 粒子反粒子 / Fine-mesh multi-anode photon-tube / Focussing DIRC / Aerogel Cerenkov / Gas Cerenkov
Research Abstract

1. Physics reserch for Direct CP Violation
Studies of direct CP violation in B-meson decays has been progressed along with accumulation of data at KEKB/Belle experiment. We succeeded to identify B→DK, D^*K, Dπ and D^*π sugbaks sebsutuve ti φ_3 angle in KM CP-triangle and measured their branching ratios. The CP asymmetry in B→Kp decay is also observed as -0.22<A_<CP>(B^0→Kπ^±+Kπ^0)<0.25. We have looked for a signal of new physics in rae B-meson decays and the branching ratio of B→Kηηwas mesured for the first time as (0.99±0.36±0.12)×10^<-6>.
Concerning to tau-lepton physics, we have examined a violation of CP/T invariance in ters of tau's EDM and resulted in a ten times higher sensitivity than previous measurement as dπ < 2×10^<-7>e ・ cm. We also looked for lepton flavor violation π→μγ decay and reached to the most sensitive upper-limit of 1.0×10^<-6>.
In the final year, we have organized the international conference of "B Physics and CP Violation (BCP4)" at Ise, Shima, and reported and discussed our outcomes from this project. In 2001 we have held a symposium "The Lost AntiWorld" under the 『University and Science』 public lecture series managed by NEXT at sendai to report our reserch to public. The both meeting were carried out quite successfully.
2. R&D for new detectors
We, Nagoya group, invented a new type of ring imaging Cherenkov counter named as TOP counter, and studied its basic performances. A silica aerogel RICH detector and a Gas cherenkov counter were examined by KEK group and Osaka-city group, respectively. Using test pulsers and beams the basic properties of these detectors were investigated.

Report

(5 results)
  • 2001 Final Research Report Summary
  • 2000 Annual Research Report
  • 1999 Annual Research Report
  • 1998 Annual Research Report
  • 1997 Annual Research Report
  • Research Products

    (28 results)

All Other

All Publications (28 results)

  • [Publications] M.Akatsu 他: "Time of propagation Cherenkov counter for particle identification"Nucl.Instr.and Methods. A440. 124 (2000)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2001 Final Research Report Summary
  • [Publications] T.Ohshima: "Test resolts of Time-of-Propagation Cherenkov counter"Nucl.Instr.and Methods. A453. 331 (2000)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2001 Final Research Report Summary
  • [Publications] K.Abe 他: "Measurement of Branching Fractions for B→ππ,Kπ and KK Decays"Phys.Rev.Lett.. 87. 101801 (2001)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2001 Final Research Report Summary
  • [Publications] K.Abe 他: "Observation of Cabibbo suppressed B→D^*K^- decays at Belle"Phys.Rev.Lett.. 87. 111801 (2001)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2001 Final Research Report Summary
  • [Publications] K.Abe 他: "Search for Direct CP Violation in B→Kπ Decays"Phys.Rev.. D64. 071101 (2001)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2001 Final Research Report Summary
  • [Publications] K.Abe 他: "Observation of the Decay B→Kl^+l^-"Phys.Rev.Lett.. 88. 021801 (2002)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      2001 Final Research Report Summary
  • [Publications] M. Akatsu et al.: "Time of Propagation Cherenkov counter for particle identification"Nucl. Instr. And Methods. A440. 124 (2000)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2001 Final Research Report Summary
  • [Publications] T. Ohshima: "Test results of Time-of-Propagation Cherenkov counter"Nucl. Instr. And Methods. A453. 331 (2000)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2001 Final Research Report Summary
  • [Publications] K. Abe et al.: "Measurement of Branching Fractions for B→ππ, Kπ and KK Decays"Phys. Rev. Lett.. 87. 101801 (2001)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2001 Final Research Report Summary
  • [Publications] K. Abe et al.: "Observation of Cabibbo suppressed B→D^*K^- Decays"Phys. Rev. Lett.. 87. 111801 (2001)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2001 Final Research Report Summary
  • [Publications] K. Abe et al.: "Search for Direct CP Violation in B→Kπ Decays"Phys. Rev.. D64. 071101 (2001)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2001 Final Research Report Summary
  • [Publications] K. Abe et al.: "Observation of the Decay B→Kμμ"Phys. Rev. Lett.. 88. 021801 (2002)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      2001 Final Research Report Summary
  • [Publications] M,Akatsu 他: "Time of propagation cherenkov counter for Particle identification"Nucl.Instr.and Methods. A440. 124 (2000)

    • Related Report
      2000 Annual Research Report
  • [Publications] T,Ohshima: "Test results of Time-of-Propagation Cherenkov counter"Nucl.Instr.and Methods. A453. 331 (2000)

    • Related Report
      2000 Annual Research Report
  • [Publications] A,Abashian 他: "Observation of the Cabibbo suppressed B→D^<(x)>K decay at Belle"Phys.Rev.Letter. (発表予定).

    • Related Report
      2000 Annual Research Report
  • [Publications] A.Abaslcian 他: "CP/T Test with Tau Leptons at Belle"Phys.Rev.Letter. (発表予定).

    • Related Report
      2000 Annual Research Report
  • [Publications] A.Abashian 他: "Searh for CP violation in τ semi-leptonic decay τ^±→π^±π°ντ"Phys.Rev.Letter. (発表予定).

    • Related Report
      2000 Annual Research Report
  • [Publications] T.Iijima 他: "Aerogel Cherenkov Counter for the Belle detector"Nucl.Instr.and Methods. A453. 321 (2000)

    • Related Report
      2000 Annual Research Report
  • [Publications] T. Ohshima: "Tau physics at BELLE"Nucl. Phys.. B(Proc. Suppl)76. 487-493 (1999)

    • Related Report
      1999 Annual Research Report
  • [Publications] N. Khalatyan, T. Abe, Y. Kato, A. Sugiyama, K. Takahashi他: "Designing of Stereo-Wire Geometry for a long Cylindrical Drift Chamber with Small Jet Cells"Nucl. Inst. and Methods. A428. 403-412 (1999)

    • Related Report
      1999 Annual Research Report
  • [Publications] M. Akatsu, M. Aoki, K. Fujimoto et al.: "Time-of-Propagation Cherankov counter for particle identification"Accepted for publication in Nucl. Instr. and Methods. A440. 124-135 (2000)

    • Related Report
      1999 Annual Research Report
  • [Publications] S. Suzuki: "Status of BELLE"Proceedings of Heavy Flavours 8 Southampton UK. (1999)

    • Related Report
      1999 Annual Research Report
  • [Publications] T. Ohshima: "Test Result of Time-of-Propagation Cherenkov Counter"Proceedings of 7th IEEE Conf. INSTR99, 浜松. (2000)

    • Related Report
      1999 Annual Research Report
  • [Publications] T.Ohshima 他4名: "Examination of OF T/CP 1nvariance in the e^+e^-→e^+e^- Reaction." Prog.Theo.Phys.99. 413-421 (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] K.Fujimoto 他5名: "A Simple Wire-Tension Measurement System" Jpn.J.Appl.Phys.37. 2068-2069 (1998)

    • Related Report
      1998 Annual Research Report
  • [Publications] T.Ohshima: "Tau physics at BELLE,Proceedings of the Fifth Int.Workshop on tau Lepton Physics.14-17Sep.1998,Santander,SPAIN"

    • Related Report
      1998 Annual Research Report
  • [Publications] T.Ohshima: "Examination of T/CP Invariance in the e^+e^-→τ^+τ^-Reaction" PROGRESS OF THEORETICAL PHYSICS. Vol.99 NO.3(3月掲載). (1998)

    • Related Report
      1997 Annual Research Report
  • [Publications] T.Ohshima: "A Simple Wire-Tension Mesurement System" Japanese Journal of Applied Physics,Part I. Vol.37 No.4(掲載予定). (1998)

    • Related Report
      1997 Annual Research Report

URL: 

Published: 1997-04-01   Modified: 2016-04-21  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi