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arXiv · 1203.6409

Evidence for CP Violation in the Decay $D^+\rightarrow K^0_S\pi^+$

B. R. Ko·E. Won·I. Adachi·H. Aihara·D. M. Asner·V. Aulchenko·T. Aushev·T. Aziz·A. M. Bakich·K. Belous·V. Bhardwaj·B. Bhuyan·M. Bischofberger·A. Bondar·G. Bonvicini·A. Bozek·M. Bra\v·T. E. Browder·M. -C. Chang·A. Chen·P. Chen·B. G. Cheon·K. Chilikin·I. -S. Cho·K. Cho·Y. Choi·Z. Dole\v·Z. Drásal·S. Eidelman·J. E. Fast·V. Gaur·N. Gabyshev·Y. M. Goh·B. Golob·J. Haba·K. Hayasaka·H. Hayashii·Y. Horii·Y. Hoshi·W. -S. Hou·H. J. Hyun·T. Iijima·A. Ishikawa·R. Itoh·M. Iwabuchi·Y. Iwasaki·T. Iwashita·T. Julius·J. H. Kang·T. Kawasaki·C. Kiesling·H. O. Kim·J. B. Kim·K. T. Kim·M. J. Kim·Y. J. Kim·K. Kinoshita·S. Koblitz·P. Kody\v·S. Korpar·P. Kri\v·P. Krokovny·T. Kuhr·A. Kuzmin·Y. -J. Kwon·J. S. Lange·S. -H. Lee·J. Li·Y. Li·J. Libby·C. -L. Lim·C. Liu·Y. Liu·Z. Q. Liu·D. Liventsev·R. Louvot·Y. Miyazaki·R. Mizuk·G. B. Mohanty·A. Moll·T. Mori·N. Muramatsu·Y. Nagasaka·E. Nakano·M. Nakao·H. Nakazawa·Z. Natkaniec·S. Nishida·K. Nishimura·O. Nitoh·S. Ogawa·T. Ohshima·S. Okuno·S. L. Olsen·Y. Onuki·W. Ostrowicz·P. Pakhlov·G. Pakhlova·C. W. Park·H. K. Park
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Abstract

We observe evidence for CP violation in the decay $D^+\rightarrow K^0_S\pi^+$ using a data sample with an integrated luminosity of 977 fb$^{-1}$ collected by the Belle detector at the KEKB $e^+e^-$ asymmetric-energy collider. The CP asymmetry in the decay is measured to be $(-0.363\pm0.094\pm0.067)%$, which is 3.2 standard deviations away from zero, and is consistent with the expected CP violation due to the neutral kaon in the final state.

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B. R. Ko, E. Won, I. Adachi, H. Aihara, D. M. Asner, V. Aulchenko, T. Aushev, T. Aziz, A. M. Bakich, K. Belous, V. Bhardwaj, B. Bhuyan, M. Bischofberger, A. Bondar, G. Bonvicini, A. Bozek, M. Bra\v, T. E. Browder, M. -C. Chang, A. Chen, P. Chen, B. G. Cheon, K. Chilikin, I. -S. Cho, K. Cho, Y. Choi, Z. Dole\v, Z. Drásal, S. Eidelman, J. E. Fast, V. Gaur, N. Gabyshev, Y. M. Goh, B. Golob, J. Haba, K. Hayasaka, H. Hayashii, Y. Horii, Y. Hoshi, W. -S. Hou, H. J. Hyun, T. Iijima, A. Ishikawa, R. Itoh, M. Iwabuchi, Y. Iwasaki, T. Iwashita, T. Julius, J. H. Kang, T. Kawasaki, C. Kiesling, H. O. Kim, J. B. Kim, K. T. Kim, M. J. Kim, Y. J. Kim, K. Kinoshita, S. Koblitz, P. Kody\v, S. Korpar, P. Kri\v, P. Krokovny, T. Kuhr, A. Kuzmin, Y. -J. Kwon, J. S. Lange, S. -H. Lee, J. Li, Y. Li, J. Libby, C. -L. Lim, C. Liu, Y. Liu, Z. Q. Liu, D. Liventsev, R. Louvot, Y. Miyazaki, R. Mizuk, G. B. Mohanty, A. Moll, T. Mori, N. Muramatsu, Y. Nagasaka, E. Nakano, M. Nakao, H. Nakazawa, Z. Natkaniec, S. Nishida, K. Nishimura, O. Nitoh, S. Ogawa, T. Ohshima, S. Okuno, S. L. Olsen, Y. Onuki, W. Ostrowicz, P. Pakhlov, G. Pakhlova, C. W. Park, H. K. Park. 2012-03-29. Evidence for CP Violation in the Decay $D^+\rightarrow K^0_S\pi^+$. https://doi.org/10.1103/physrevlett.109.021601

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