Options
Measurement of the branching fraction and CP asymmetry in B<sup>0</sup> → π<sup>0</sup>π<sup>0</sup> decays, and an improved constraint on ϕ<inf>2</inf>
Date Issued
01-12-2017
Author(s)
Julius, T.
Sevior, M. E.
Mohanty, G. B.
Adachi, I.
Aihara, H.
Al Said, S.
Asner, D. M.
Aulchenko, V.
Aushev, T.
Ayad, R.
Babu, V.
Badhrees, I.
Bakich, A. M.
Bansal, V.
Barberio, E.
Barrett, M.
Berger, M.
Bhardwaj, V.
Bhuyan, B.
Biswal, J.
Bloomfield, T.
Bobrov, A.
Bondar, A.
Bonvicini, G.
Bozek, A.
BraÄ ko, M.
Browder, T. E.
ÄŒervenkov, D.
Chang, M. C.
Chao, Y.
Chekelian, V.
Chen, A.
Cheon, B. G.
Chilikin, K.
Cho, K.
Choi, Y.
Cinabro, D.
Dash, N.
Di Carlo, S.
Doležal, Z.
Dossett, D.
Drásal, Z.
Dutta, D.
Eidelman, S.
Farhat, H.
Fast, J. E.
Ferber, T.
Fulsom, B. G.
Gaur, V.
Gabyshev, N.
Garmash, A.
Gillard, R.
Goldenzweig, P.
Haba, J.
Hara, T.
Hayasaka, K.
Hayashii, H.
Hou, W. S.
Hsu, C. L.
Iijima, T.
Inami, K.
Ishikawa, A.
Itoh, R.
Iwasaki, Y.
Jacobs, W. W.
Jaegle, I.
Jin, Y.
Joffe, D.
Joo, K. K.
Kahn, J.
Karyan, G.
Katrenko, P.
Kawasaki, T.
Kiesling, C.
Kim, D. Y.
Kim, H. J.
Kim, J. B.
Kim, K. T.
Kim, M. J.
Kim, S. H.
Kim, Y. J.
Kinoshita, K.
Kodyš, P.
Korpar, S.
Kotchetkov, D.
Križan, P.
Krokovny, P.
Krohn, J. F.
Kuhr, T.
Kulasiri, R.
Kuzmin, A.
Kwon, Y. J.
Lange, J. S.
Lee, I. S.
Li, C. H.
Li, L.
Li, Y.
Li Gioi, L.
Indian Institute of Technology, Madras
Liventsev, D.
Abstract
We measure the branching fraction and CP violation asymmetry in the decay B0 → π0π0, using a data sample of 752 × 106 BB¯ pairs collected at the ϒð4SÞ resonance with the Belle detector at the KEKB eþe− collider. The obtained branching fraction and direct CP asymmetry are BðB → π0π0Þ ¼ ½1.31 0.19ðstatÞ 0.19ðsystÞ × 10−6 and ACP ¼ þ0.14 0.36ðstatÞ 0.10ðsystÞ, respectively. The signal significance, including the systematic uncertainty, is 6.4 standard deviations. We combine these results with Belle’s earlier measurements of B0 → πþπ− and B → ππ0 to exclude the CP-violating parameter ϕ2 from the range 15.5° < ϕ2 < 75.0° at 95% confidence level.
Volume
96