Belle CollaborationTien, K. -J.Wang, M. -Z.Adachi, I.Aihara, H.Asner, D. M.Aulchenko, V.Aushev, T.Bakich, A. M.Bala, A.Bhuyan, B.Bozek, A.Bracko, M.Browder, T. E.Chang, P.Chekelian, V.Chen, A.Chen, P.Cheon, B. G.Chilikin, K.Chistov, R.Cho, I. -S.Cho, K.Chobanova, V.Choi, Y.Cinabro, D.Dalseno, J.Danilov, M.Dolezal, Z.Drasal, Z.Dutta, D.Eidelman, S.Farhat, H.Fast, J. E.Ferber, T.Gaur, V.Ganguly, S.Gillard, R.Goh, Y. M.Golob, B.Haba, J.Hayashii, H.Horii, Y.Hoshi, Y.Hou, W. -S.Hsiung, Y. B.Huschle, M.Hyun, H. J.Iijima, T.Ishikawa, A.Itoh, R.Iwasaki, Y.Julius, T.Kah, D. H.Kang, J. H.Kato, E.Kawasaki, T.Kichimi, H.Kiesling, C.Kim, D. Y.Kim, H. J.Kim, J. B.Kim, J. H.Kim, Y. J.Klucar, J.Ko, B. R.Kodys, P.Korpar, S.Krizan, P.Krokovny, P.Kronenbitter, B.Kuhr, T.Kumita, T.Kuzmin, A.Kwon, Y. -J.Lee, S. -H.Li, J.Li, Y.Libby, J.Liu, C.Liu, Y.Liventsev, D.Lukin, P.Miyabayashi, K.Miyata, H.Mohanty, G. B.Moll, A.Mussa, R.Nakano, E.Nakao, M.Natkaniec, Z.Nayak, M.Nedelkovska, E.Ng, C.Nisar, N. K.Nishida, S.Nitoh, O.Ogawa, S.Okuno, S.Olsen, S. L.Ostrowicz, W.Oswald, C.Park, C. W.Park, H.Park, H. K.Pedlar, T. K.Pestotnik, R.Petric, M.Piilonen, L. E.Ritter, M.Roehrken, M.Rostomyan, A.Sahoo, H.Saito, T.Sakai, Y.Sandilya, S.Santel, D.Santelj, L.Sanuki, T.Sato, Y.Savinov, V.Schneider, O.Schnell, G.Schwanda, C.Semmler, D.Senyo, K.Seon, O.Sevior, M. E.Shapkin, M.Shen, C. P.Shibata, T. -A.Shiu, J. -G.Sibidanov, A.Sohn, Y. -S.Sokolov, A.Stanic, S.Staric, M.Steder, M.Sumihama, M.Sumiyoshi, T.Tanida, K.Tatishvili, G.Teramoto, Y.Uchida, M.Uehara, S.Uglov, T.Unno, Y.Uno, S.Urquijo, P.Vahsen, S. E.Van Hulse, C.Vanhoefer, P.Varner, G.Varvell, K. E.Vinokurova, A.Vorobyev, V.Wagner, M. N.Wang, C. H.Wang, P.Watanabe, M.Watanabe, Y.Williams, K. M.Won, E.Yamaoka, J.Yamashita, Y.Yashchenko, S.Zhang, Z. P.Zhilich, V.Zhulanov, V.Zupanc, A.2014-04-022014-04-022014-04-02201410.1103/PhysRevD.89.011101https://infoscience.epfl.ch/handle/20.500.14299/102476WOS:000331841100001We find evidence for the semileptonic baryonic decay B- -> p (p) over barl(-)(nu) over bar (l) (l = e, mu), based on a data sample of 772 million B (B) over bar pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy electron-positron collider. A neural-network based hadronic B-meson tagging method is used in this study. The branching fraction of B- -> p (p) over barl(-)(nu) over bar (l) is measured to be (5.8(-2.1)(+2.4)(stat) +/- 0.9(syst)) x 10(-6) with a significance of 3.2 sigma s, where lepton universality is assumed. We also estimate the corresponding upper limit: B(B- -> p (p) over barl(-)(nu) over bar (l)) < 9.6 x 10(-6) at the 90% confidence level. This measurement helps constrain the baryonic transition form factor in B decays.text::journal::journal article::research article