학술논문

Measurement of branching fractions for B \to J/\psi \eta K decays and search for a narrow resonance in the J/\psi \eta final state
Document Type
Working Paper
Author
Belle CollaborationIwashita, 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.Bračko, 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.Kodyš, P.Korpar, S.Križan, P.Krokovny, P.Kuhr, T.Kumita, T.Kuzmin, A.Kwon, Y. -J.Lange, J. S.Lee, S. -H.Li, Y.Libby, J.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.Nisar, N. K.Nishida, S.Nitoh, O.Ogawa, S.Okuno, S.Pakhlova, G.Panzenbock, E.Park, H.Park, H. K.Pedlar, T. K.Pestotnik, R.Petrič, M.Piilonen, L. E.Ritter, M.Rohrken, M.Rostomyan, A.Ryu, S.Sahoo, H.Saito, T.Sakai, K.Sakai, Y.Sandilya, S.Santel, D.Santelj, L.Sanuki, T.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.Shwartz, B.Sibidanov, A.Simon, F.Sohn, Y. -S.Sokolov, A.Solovieva, E.Stanic, S.Starič, M.Steder, M.Sumiyoshi, T.Tamponi, U.Tanida, K.Tatishvili, G.Teramoto, Y.Trabelsi, K.Tsuboyama, T.Uchida, M.Uehara, S.Unno, Y.Uno, S.Urquijo, P.Vanhoefer, P.Varner, G.Varvell, K. E.Vorobyev, V.Vossen, A.Wagner, M. N.Wang, C. H.Wang, M. -Z.Wang, P.Wang, X. L.Watanabe, M.Watanabe, Y.Williams, K. M.Won, E.Yabsley, B. D.Yamashita, Y.Yashchenko, S.Yook, Y.Yuan, C. Z.Zhang, Z. P.Zhilich, V.Zupanc, A.
Source
Subject
High Energy Physics - Experiment
Language
Abstract
We report an observation of the $B^{\pm} \to J/\psi \eta K^{\pm}$ and $B^0 \to J/\psi \eta K^0_S$ decays using 772$\times 10^{6}$ $B\bar{B}$ pairs collected at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. We obtain the branching fractions ${\cal B}(B^{\pm}\rightarrow J/\psi\eta K^{\pm})=(1.27\pm 0.11{\rm (stat.)\pm 0.11{\rm (syst.)})}\times10^{-4}$ and ${\cal B}(B^0\to J/\psi \eta K^0_S)=(5.22 \pm 0.78 {\rm(stat.)} \pm 0.49{\rm(syst.)})\times10^{-5}$. We search for a new narrow charmonium(-like) state $X$ in the $J/\psi \eta$ mass spectrum and find no significant excess. We set upper limits on the product of branching fractions, ${\cal B}(B^\pm \to XK^\pm){\cal B}(X \to J/\psi \eta)$, at 3872 MeV$/c^2$ where a $C$-odd partner of X(3872) may exist, at $\psi(4040)$ and $\psi(4160)$ assuming their known mass and width, and over a range from 3.8 to 4.8 GeV$/c^2$. % at a 5 MeV$/c^2$ step. The obtained upper limits at 90% confidence level for $X^{C{\rm -odd}}(3872)$, $\psi(4040)$ and $\psi(4160)$ are 3.8$\times 10^{-6}$, 15.5$\times 10^{-6}$ and 7.4$\times 10^{-6}$, respectively.
Comment: Submitted to PTEP