Grant-in-Aid for Scientific Research on Priority Areas (A).
|Research Institution||Nagoya University|
OHSHIMA Takayoshi Nagoya University, Department of Physics Professor, 大学院・理学研究科, 教授 (00134651)
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)
TAKAHASHI Tamotsu Osaka-city Univ. Dep. of Physics, Prof., 理学部, 教授 (20047137)
宮林 謙吉 奈良女子大学, 理学部, 助手 (40273833)
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)
杉山 晃 名古屋大学, 大学院・理学研究科, 助手 (80187674)
NITOH Osamu Tokyo Univ. of Agriculture and Technology, Dep. Of Applied Physics, Ass. Prof., 工学部, 助教授 (00189333)
|Project Fiscal Year
1997 – 2000
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)
|Keywords||Direct CP Violation / Kobayashi-Maskaa Matrix / φ_3 CP-Angle / T-lepton's CP Vidaton / Partide Identification / Cherenkov Radiation / 直接的CP非保存 / 小林・益川行列 / φ_3偏角 / タウ・レプトンのCP非保存 / 粒子識別 / チェレンコフ放射 / 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|
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.