Journal article

Evidence of time-dependent CP violation in the decay B-0 -> D* D*-

K Vervink, T Aushev, O Schneider, K Arinstein, AM Bakich, V Balagura, E Barberio, A Bay, V Bhardwaj, U Bitenc, A Bondar, A Bozek, M Bracko, J Brodzicka, TE Browder, Y Chao, A Chen, BG Cheon, C-C Chiang, R Chistov Show all

Physical Review D | AMER PHYSICAL SOC | Published : 2009


We report a measurement of the CP-odd fraction and the time-dependent CP violation in B0→D*+D*- decays, using 657×106 BB̄ events collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We measure a CP-odd fraction of R=0.125±0.043(stat)±0.023(syst). From the distributions of the proper-time intervals between a B0→D*+D*- decay and the other B meson in the event, we obtain evidence of CP violation with measured parameters AD*+D*-=0.15±0.13(stat)±0.04(syst) and SD*+D*-=-0.96±0.25(stat)-0.16+0.13(syst). © 2009 The American Physical Society.


Awarded by National Natural Science Foundation of China

Awarded by Korea Science and Engineering Foundation

Awarded by Korea Research Foundation

Funding Acknowledgements

We thank the KEKB Group for the excellent operation of the accelerator, the KEK cryogenics group for the efficient operation of the solenoid, and the KEK computer group and the National Institute of Informatics for valuable computing and SINET3 network support. We acknowledge support from the Ministry of Education, Culture, Sports, Science, and Technology (MEXT) of Japan, the Japan Society for the Promotion of Science (JSPS), and the Tau-Lepton Physics Research Center of Nagoya University; the Australian Research Council and the Australian Department of Industry, Innovation, Science and Research; the National Natural Science Foundation of China under Contract Nos. 10575109, 10775142, 10875115, and 10825524; the Department of Science and Technology of India; the BK21 and WCU program of the Ministry Education Science and Technology, the CHEP SRC program and Basic Research program (Grant No. R01-2008-000-10477-0) of the Korea Science and Engineering Foundation, Korea Research Foundation (Contract No. KRF-2008-313-C00177), and the Korea Institute of Science and Technology Information; the Polish Ministry of Science and Higher Education; the Ministry of Education and Science of the Russian Federation and the Russian Federal Agency for Atomic Energy; the Slovenian Research Agency; the Swiss National Science Foundation; the National Science Council and the Ministry of Education of Taiwan; and the U. S. Department of Energy. This work is supported by a Grant-in-Aid from MEXT for Science Research in a Priority Area (''New Development of Flavor Physics''), and from JSPS for Creative Scientific Research (''Evolution of Tau-lepton Physics'').