Precise measurement of the CP violation parameter sin 2Φ1 in B0 → (c$\bar{c}$)K0 decays

• Published in: Physical review letters 2012-04, Vol.108 (17)
• Main Authors: Aihara, H., Aulchenko, V., Aushev, T., Bhardwaj, V., Bozek, A., Bračko, M., Chen, P., Cheon, B. G., Cho, K., Choi, S. -K., Choi, Y., Danilov, M., Doležal, Z., Epifanov, D., Fast, J. E., Gabyshev, N., Haba, J., Hara, T., Hayasaka, K., Higuchi, T., Horii, Y., Itoh, R., Iwabuchi, M., Iwasaki, Y., Iwashita, T., Julius, T., Kapusta, P., Katayama, N., Kawasaki, T., Kiesling, C., Kim, H. J., Kim, J. B., Kim, K. T., Kinoshita, K., Ko, B. R., Kodyš, P., Korpar, S., Kuhr, T., Kuzmin, A., Kwon, Y. -J., Lee, S. -H., Li, J., Li, Y., Liu, Y., Matvienko, D., McOnie, S., Miyabayashi, K., Miyata, H., Miyazaki, Y., Mizuk, R., Mohanty, G. B., Nakano, E., Nakazawa, H., Nishida, S., Nitoh, O., Ogawa, S., Onuki, Y., Ozaki, H., Park, K. S., Petrič, M., Piilonen, L. E., Poluektov, A., Röhrken, M., Rozanska, M., Sakai, K., Sakai, Y., Sato, Y., Shibata, T. -A., Shiu, J. -G., Sibidanov, A., Singh, J. B., Smerkol, P., Sokolov, A., Stanič, S., Starič, M., Sumihama, M., Sumisawa, K., Teramoto, Y., Tikhomirov, I., Uchida, M., Unno, Y., Ushiroda, Y., Vahsen, S. E., Varner, G., Vinokurova, A., Vorobyev, V., Wang, C. H., Wang, M. -Z., Watanabe, M., Watanabe, Y., Williams, K. M., Won, E., Yabsley, B. D., Yamamoto, H., Yamashita, Y., Yamauchi, M., Yusa, Y., Zhilich, V., Zupanc, A., Zyukova, O.
• Format: Article
• Language: English
• Subjects: INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
• ISSN: 0031-9007; 1079-7114
• DOI: 10.1103/PhysRevLett.108.171802

We present a precise measurement of the CP violation parameter sin2$\phi$1 and the direct CP violation parameter $A$f using the final data sample of 772×106 $B\overline{B}$ pairs collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. One neutral B meson is reconstructed in a J/ψK$0\atop{S}$, ψ(2S)K$0\atop{S}$, χc1K$0\atop{S}$, or J/ψK$0\atop{L}$ CP eigenstate and its flavor is identified from the decay products of the accompanying B meson. From the distribution of proper-time intervals between the two B decays, we obtain the following CP violation parameters: sin2 $\phi$1=0.667±0.023(stat)±0.012(syst) and $A$f=0.006±0.016(stat)±0.012(syst).