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arXiv · 1504.00957

Evidence for the decay B0->eta pi^0

Belle Collaboration·B. Pal·A. J. Schwartz·A. Abdesselam·I. Adachi·H. Aihara·S. Al Said·K. Arinstein·D. M. Asner·V. Aulchenko·T. Aushev·R. Ayad·V. Babu·I. Badhrees·A. M. Bakich·A. Bobrov·G. Bonvicini·A. Bozek·M. Bračko·T. E. Browder·D. Červenkov·M. -C. Chang·V. Chekelian·A. Chen·B. G. Cheon·K. Cho·V. Chobanova·Y. Choi·D. Cinabro·J. Dalseno·Z. Doležal·Z. Drásal·A. Drutskoy·D. Dutta·S. Eidelman·H. Farhat·J. E. Fast·T. Ferber·O. Frost·B. G. Fulsom·V. Gaur·N. Gabyshev·S. Ganguly·A . Garmash·D. Getzkow·R. Gillard·R. Glattauer·Y. M. Goh·B. Golob·O. Grzymkowska·T. Hara·K. Hayasaka·H. Hayashii·X. H. He·W. -S. Hou·M. Huschle·H. J. Hyun·T. Iijima·A. Ishikawa·R. Itoh·Y. Iwasaki·I. Jaegle·T. Julius·K. H. Kang·E. Kato·C. Kiesling·D. Y. Kim·J. B. Kim·J. H. Kim·K. T. Kim·M. J. Kim·S. H. Kim·Y. J. Kim·K. Kinoshita·B. R. Ko·P. Kodyš·S. Korpar·P. Križan·P. Krokovny·T. Kuhr·T. Kumita·A. Kuzmin·Y. -J. Kwon·J. S. Lange·D. H. Lee·I. S. Lee·Y. Li·L. Li Gioi·J. Libby·D. Liventsev·P. Lukin·D. Matvienko·H. Miyata·G. B. Mohanty·A. Moll·H. K. Moon·K. R. Nakamura·E. Nakano·M. Nakao·T. Nanut
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Abstract

We report a search for the charmless hadronic decay $B^0\to\eta \pi^0$ with a data sample corresponding to an integrated luminosity of 694 $\rm fb^{-1}$ containing $753\times10^6$ $B\bar{B}$ pairs. The data were collected by the Belle experiment running on the $\Upsilon(4S)$ resonance at the KEKB $e^+e^-$ collider. We measure a branching fraction $\mathcal{B}(B^0\to\eta\pi^0)=(4.1^{+1.7+0.5}_{-1.5-0.7})\times 10^{-7}$, where the first uncertainty is statistical and the second is systematic. Our measurement gives an upper limit of $\mathcal{B}(B^0\to\eta\pi^0)<6.5\times 10^{-7}$ at 90\% confidence level. The signal has a significance of $3.0$ standard deviations and constitutes the first evidence for this decay mode.

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Belle Collaboration, B. Pal, A. J. Schwartz, A. Abdesselam, I. Adachi, H. Aihara, S. Al Said, K. Arinstein, D. M. Asner, V. Aulchenko, T. Aushev, R. Ayad, V. Babu, I. Badhrees, A. M. Bakich, A. Bobrov, G. Bonvicini, A. Bozek, M. Bračko, T. E. Browder, D. Červenkov, M. -C. Chang, V. Chekelian, A. Chen, B. G. Cheon, K. Cho, V. Chobanova, Y. Choi, D. Cinabro, J. Dalseno, Z. Doležal, Z. Drásal, A. Drutskoy, D. Dutta, S. Eidelman, H. Farhat, J. E. Fast, T. Ferber, O. Frost, B. G. Fulsom, V. Gaur, N. Gabyshev, S. Ganguly, A . Garmash, D. Getzkow, R. Gillard, R. Glattauer, Y. M. Goh, B. Golob, O. Grzymkowska, T. Hara, K. Hayasaka, H. Hayashii, X. H. He, W. -S. Hou, M. Huschle, H. J. Hyun, T. Iijima, A. Ishikawa, R. Itoh, Y. Iwasaki, I. Jaegle, T. Julius, K. H. Kang, E. Kato, C. Kiesling, D. Y. Kim, J. B. Kim, J. H. Kim, K. T. Kim, M. J. Kim, S. H. Kim, Y. J. Kim, K. Kinoshita, B. R. Ko, P. Kodyš, S. Korpar, P. Križan, P. Krokovny, T. Kuhr, T. Kumita, A. Kuzmin, Y. -J. Kwon, J. S. Lange, D. H. Lee, I. S. Lee, Y. Li, L. Li Gioi, J. Libby, D. Liventsev, P. Lukin, D. Matvienko, H. Miyata, G. B. Mohanty, A. Moll, H. K. Moon, K. R. Nakamura, E. Nakano, M. Nakao, T. Nanut. 2015-04-03. Evidence for the decay B0->eta pi^0. https://doi.org/10.1103/physrevd.92.011101

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