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arXiv · 1201.4643

Precise measurement of the CP violation parameter sin2phi_1 in B0-->(c\bar c)K0 decays

Belle Collaboration·I. Adachi·H. Aihara·D. M. Asner·V. Aulchenko·T. Aushev·T. Aziz·A. M. Bakich·A. Bay·V. Bhardwaj·B. Bhuyan·M. Bischofberger·A. Bondar·A. Bozek·M. Bracko·T. E. Browder·P. Chen·B. G. Cheon·K. Chilikin·R. Chistov·K. Cho·S. -K. Choi·Y. Choi·J. Dalseno·M. Danilov·Z. Dolezal·Z. Drasal·S. Eidelman·D. Epifanov·J. E. Fast·V. Gaur·N. Gabyshev·A. Garmash·Y. M. Goh·B. Golob·J. Haba·K. Hara·T. Hara·K. Hayasaka·H. Hayashii·T. Higuchi·Y. Horii·Y. Hoshi·W. -S. Hou·Y. B. Hsiung·H. J. Hyun·T. Iijima·A. Ishikawa·R. Itoh·M. Iwabuchi·Y. Iwasaki·T. Iwashita·T. Julius·P. Kapusta·N. Katayama·T. Kawasaki·H. Kichimi·C. Kiesling·H. J. Kim·H. O. Kim·J. B. Kim·J. H. Kim·K. T. Kim·Y. J. Kim·K. Kinoshita·B. R. Ko·S. Koblitz·P. Kodyš·S. Korpar·P. Krizan·P. Krokovny·T. Kuhr·R. Kumar·T. Kumita·A. Kuzmin·Y. -J. Kwon·J. S. Lange·S. -H. Lee·J. Li·Y. Li·C. Liu·Y. Liu·Z. Q. Liu·D. Liventsev·R. Louvot·D. Matvienko·S. McOnie·K. Miyabayashi·H. Miyata·Y. Miyazaki·R. Mizuk·G. B. Mohanty·T. Mori·N. Muramatsu·E. Nakano·M. Nakao·H. Nakazawa·S. Neubauer·S. Nishida·K. Nishimura
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Abstract

We present a precise measurement of the CP violation parameter sin2phi_1 and the direct CP violation parameter A_f using the final data sample of 772x10^6 B\bar B pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. One neutral B meson is reconstructed in a J/psi K0S, psi(2S) K0S, chi_c1 K0S or J/psi K0L 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: sin2phi_1=0.667+-0.023(stat)+-0.012(syst) and A_f=0.006+-0.016(stat)+-0.012(syst).

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Belle Collaboration, I. Adachi, H. Aihara, D. M. Asner, V. Aulchenko, T. Aushev, T. Aziz, A. M. Bakich, A. Bay, V. Bhardwaj, B. Bhuyan, M. Bischofberger, A. Bondar, A. Bozek, M. Bracko, T. E. Browder, P. Chen, B. G. Cheon, K. Chilikin, R. Chistov, K. Cho, S. -K. Choi, Y. Choi, J. Dalseno, M. Danilov, Z. Dolezal, Z. Drasal, S. Eidelman, D. Epifanov, J. E. Fast, V. Gaur, N. Gabyshev, A. Garmash, Y. M. Goh, B. Golob, J. Haba, K. Hara, T. Hara, K. Hayasaka, H. Hayashii, T. Higuchi, Y. Horii, Y. Hoshi, W. -S. Hou, Y. B. Hsiung, H. J. Hyun, T. Iijima, A. Ishikawa, R. Itoh, M. Iwabuchi, Y. Iwasaki, T. Iwashita, T. Julius, P. Kapusta, N. Katayama, T. Kawasaki, H. Kichimi, C. Kiesling, H. J. Kim, H. O. Kim, J. B. Kim, J. H. Kim, K. T. Kim, Y. J. Kim, K. Kinoshita, B. R. Ko, S. Koblitz, P. Kodyš, S. Korpar, P. Krizan, P. Krokovny, T. Kuhr, R. Kumar, T. Kumita, A. Kuzmin, Y. -J. Kwon, J. S. Lange, S. -H. Lee, J. Li, Y. Li, C. Liu, Y. Liu, Z. Q. Liu, D. Liventsev, R. Louvot, D. Matvienko, S. McOnie, K. Miyabayashi, H. Miyata, Y. Miyazaki, R. Mizuk, G. B. Mohanty, T. Mori, N. Muramatsu, E. Nakano, M. Nakao, H. Nakazawa, S. Neubauer, S. Nishida, K. Nishimura. 2012-01-23. Precise measurement of the CP violation parameter sin2phi_1 in B0-->(c\bar c)K0 decays. https://doi.org/10.1103/physrevlett.108.171802

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