Evidence for CP violation in B0-->D+D- decays.

/ Authors

S. Fratina, K. Abe, I. Adachi, H. Aihara, D. Anipko, K. Arinstein, T. Aushev, A. Bakich, E. Barberio, A. Bay

and 146 more authors

K. Belous, U. Bitenc, I. Bizjak, A. Bondar, A. Bozek, M. Bračko, J. Brodzicka, T. Browder, M. Chang, P. Chang, Y. Chao, A. Chen, K.F. Chen, W. Chen, B. Cheon, R. Chistov, Y. Choi, Y. Choi, S. Cole, J. Dalseno, M. Dash, A. Drutskoy, S. Eidelman, A. Go, B. Golob, A. Gorišek, H. Ha, J. Haba, K. Hara, M. Hazumi, D. Heffernan, T. Hokuue, Y. Hoshi, W. Hou, T. Iijima, K. Inami, A. Ishikawa, H. Ishino, R. Itoh, M. Iwasaki, Y. Iwasaki, H. Kaji, J. Kang, N. Katayama, H. Kawai, T. Kawasaki, H. Kichimi, H. Kim, H. Kim, S. Kim, Y. Kim, K. Kinoshita, S. Korpar, P. Križan, P. Krokovny, R. Kulasiri, R. Kumar, C. Kuo, A. Kuzmin, Y. Kwon, M. Lee, S. Lee, T. Lesiak, A. Limosani, S. Lin, D. Liventsev, F. Mandl, T. Matsumoto, A. Matyja, S. Mconie, T. Medvedeva, W. Mitaroff, K. Miyabayashi, H. Miyake, H. Miyata, Y. Miyazaki, R. Mizuk, G. Moloney, T. Mori, E. Nakano, M. Nakao, H. Nakazawa, S. Nishida, S. Noguchi, S. Ogawa, T. Ohshima, S. Okuno, S. Olsen, Y. Onuki, H. Ozaki, P. Pakhlov, G. Pakhlova, C. Park, H. Park, L. Peak, R. Pestotnik, L. Piilonen, Y. Sakai, N. Satoyama, T. Schietinger, O. Schneider, J. Schümann, C. Schwanda, A. Schwartz, K. Senyo, M. Sevior, M. Shapkin, H. Shibuya, B. Shwartz, J. B. Singh, A. Somov, N. Soni, S. Stanič, M. Starič, H. Stoeck, T. Sumiyoshi, F. Takasaki, K. Tamai, M. Tanaka, Y. Teramoto, X. Tian, I. Tikhomirov, K. Trabelsi, T. Tsukamoto, S. Uehara, K. Ueno, T. Uglov, Y. Unno, S. Uno, P. Urquijo, Y. Usov, G. Varner, K. Varvell, K. Vervink, S. Villa, C. Wang, Y. Watanabe, E. Won, B. Yabsley, A. Yamaguchi, Y. Yamashita, M. Yamauchi, C. Zhang, Z. Zhang, V. Zhilich, A. Zupanc

/ Abstract

We report measurements of the branching fraction and CP violation parameters in B(0)-->D+ D- decays. The results are based on a data sample that contains 535 x 10(6) BB pairs collected at the Upsilon(4S) resonance, with the Belle detector at the KEKB asymmetric-energy e+e- collider. We obtain [1.97+/-0.20(stat) +/- 0.20(syst)] x 10(-4) for the branching fraction of B0-->D+D-. The measured values of the CP violation parameters are S=-1.13+/-0.37+/-0.09, A=0.91+/-0.23+/-0.06, where the first error is statistical and the second is systematic. We find evidence of CP violation in B0-->D+D- at the 4.1sigma confidence level. While the value of S is consistent with expectations from other measurements, the value of the parameter A favors large direct CP violation at the 3.2sigma confidence level, in contradiction to standard model expectations.

Journal: Physical review letters

DOI: 10.1103/PhysRevLett.98.221802