Measurement of branching fractions for B → J/ψηK decays and search for a narrow resonance in the J/ψη final state

Date Issued
16-04-2014
Author(s)
Iwashita, T.
Miyabayashi, K.
Bhardwaj, V.
Adachi, I.
Aihara, H.
Asner, D. M.
Aushev, T.
Bakich, A. M.
Bala, A.
Bhuyan, B.
Bonvicini, G.
Bozek, A.
BraÄ ko, M.
Browder, T. E.
Chang, M. C.
Chen, A.
Cheon, B. G.
Chilikin, K.
Chistov, R.
Cho, K.
Chobanova, V.
Choi, S. K.
Choi, Y.
Cinabro, D.
Dalseno, J.
Danilov, M.
Doležal, Z.
Drásal, Z.
Dutta, D.
Eidelman, S.
Esen, S.
Farhat, H.
Fast, J. E.
Feindt, M.
Ferber, T.
Frey, A.
Gaur, V.
Gabyshev, N.
Ganguly, S.
Gillard, R.
Goh, Y. M.
Golob, B.
Haba, J.
Hara, T.
Hayasaka, K.
Hayashii, H.
Higuchi, T.
Horii, Y.
Hoshi, Y.
Hou, W. S.
Hyun, H. J.
Iijima, T.
Ishikawa, A.
Itoh, R.
Iwasaki, Y.
Jaegle, I.
Julius, T.
Kah, D. H.
Kang, J. H.
Kato, E.
Kawasaki, T.
Kichimi, H.
Kiesling, C.
Kim, D. Y.
Kim, H. J.
Kim, H. O.
Kim, J. B.
Kim, J. H.
Kim, M. J.
Kim, Y. J.
Kinoshita, K.
Klucar, J.
Ko, B. R.
Kodyšs, P.
Korpar, S.
Križan, P.
Krokovny, P.
Kuhr, T.
Kumita, T.
Kuzmin, A.
Kwon, Y. J.
Lange, J. S.
Lee, S. H.
Li, Y.
Indian Institute of Technology, Madras
Liu, C.
Liu, Y.
Lukin, P.
Matvienko, D.
Miyata, H.
Mizuk, R.
Moll, A.
Mori, T.
Nagasaka, Y.
Nakano, E.
Nakao, M.
Nakazawa, H.
Natkaniec, Z.
Nayak, M.
Ng, C.
DOI
Abstract
We report an observation of the B<sup>±</sup>→ J/ψηK<sup>±</sup> and B<sup>0</sup> → J/ψηK<sup>0</sup>S decays using 772 × 10<sup>6</sup>BB¯ pairs collected at the γ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e<sup>+</sup>e<sup>-</sup> collider. We obtain the branching fractions B(B?→ J/ψηK<sup>±</sup>) = (1.27 ±0.11(stat.) ±0.11(syst.)) ×10<sup>-4</sup> and B(B<sup>0</sup> → J/ψηK<sup>0</sup> S ) = (5.22 ±0.78(stat.) ± 0.49(syst.)) ×10<sup>-5</sup>. We search for a new narrow charmonium(-like) state X in the J/ψη mass spectrum and find no significant excess. We set upper limits on the product of branching fractions, B(B±→ X K± )B(X → J/ψη), at 3872MeVc<sup>-2</sup> where aC-odd partner of X(3872) may exist, at ψ(4040) and ψ(4160) assuming their known mass and width, and over a range from 3.8 to 4.8 GeV c<sup>-2</sup>. The obtained upper limits at 90% confidence level for X<sup>C-odd</sup>(3872), ψ(4040), and ψ(4160) are 3.8 ×10<sup>-6</sup>, 15.5 ×10<sup>-6</sup>, and 7.4 ×10<sup>-6</sup>, respectively.
Volume
2014