Evidence of $Υ(1S) \to J/ψ+χ_{c1}$ and search for double-charmonium production in $Υ(1S)$ and $Υ(2S)$ decays
Creators: name: Belle Collaboration
name: Yang, S. D.
name: Shen, C. P.
name: Ban, Y.
name: Abdesselam, A.
name: Adachi, I.
name: Aihara, H.
name: Said, S. Al
name: Arinstein, K.
name: Asner, D. M.
name: Aulchenko, V.
name: Aushev, T.
name: Ayad, R.
name: Bakich, A. M.
name: Bansal, V.
name: Behera, P.
name: Bhuyan, B.
name: Bobrov, A.
name: Bozek, A.
name: Bračko, M.
name: Browder, T. E.
name: Červenkov, D.
name: Chekelian, V.
name: Chen, A.
name: Cheon, B. G.
name: Chilikin, K.
name: Chistov, R.
name: Cho, K.
name: Chobanova, V.
name: Choi, S. -K.
name: Choi, Y.
name: Cinabro, D.
name: Dalseno, J.
name: Danilov, M.
name: Dingfelder, J.
name: Doležal, Z.
name: Drásal, Z.
name: Drutskoy, A.
name: Dutta, K.
name: Eidelman, S.
name: Farhat, H.
name: Fast, J. E.
name: Ferber, T.
name: Gaur, V.
name: Gabyshev, N.
name: Ganguly, S.
name: Garmash, A.
name: Gillard, R.
name: Goh, Y. M.
name: Golob, B.
name: Haba, J.
name: Hara, T.
name: Hayashii, H.
name: He, X. H.
name: Hou, W. -S.
name: Huschle, M.
name: Iijima, T.
name: Inami, K.
name: Ishikawa, A.
name: Itoh, R.
name: Jaegle, I.
name: Joffe, D.
name: Joo, K. K.
name: Julius, T.
name: Kawasaki, T.
name: Kim, D. Y.
name: Kim, H. J.
name: Kim, J. B.
name: Kim, J. H.
name: Kim, K. T.
name: Kinoshita, K.
name: Ko, B. R.
name: Kodyš, P.
name: Korpar, S.
name: Križan, P.
name: Krokovny, P.
name: Kuzmin, A.
name: Kwon, Y. -J.
name: Lange, J. S.
name: Li, J.
name: Li, Y.
name: Gioi, L. Li
name: Libby, J.
name: Liventsev, D.
name: Lukin, P.
name: Miyabayashi, K.
name: Miyata, H.
name: Moll, A.
name: Mussa, R.
name: Nakano, E.
name: Nakao, M.
name: Nanut, T.
name: Nisar, N. K.
name: Nishida, S.
name: Okuno, S.
name: Ostrowicz, W.
name: Park, C. W.
name: Park, H.
name: Pedlar, T. K.
name: Pestotnik, R.
name: Petrič, M.
name: Piilonen, L. E.
name: Ribežl, E.
name: Ritter, M.
name: Rostomyan, A.
name: Sakai, Y.
name: Sandilya, S.
name: Santelj, L.
name: Sanuki, T.
name: Schneider, O.
name: Schnell, G.
name: Schwanda, C.
name: Semmler, D.
name: Senyo, K.
name: Shebalin, V.
name: Shibata, T. -A.
name: Shiu, J. -G.
name: Shwartz, B.
name: Sibidanov, A.
name: Simon, F.
name: Sohn, Y. -S.
name: Sokolov, A.
name: Starič, M.
name: Steder, M.
name: Sumiyoshi, T.
name: Tamponi, U.
name: Tanida, K.
name: Tatishvili, G.
name: Teramoto, Y.
name: Uchida, M.
name: Uehara, S.
name: Uglov, T.
name: Unno, Y.
name: Uno, S.
name: Urquijo, P.
name: Usov, Y.
name: Vahsen, S. E.
name: Van Hulse, C.
name: Vanhoefer, P.
name: Varner, G.
name: Vinokurova, A.
name: Vorobyev, V.
name: Vossen, A.
name: Wagner, M. N.
name: Wang, C. H.
name: Wang, M. -Z.
name: Wang, P.
name: Wang, X. L.
name: Watanabe, M.
name: Watanabe, Y.
name: Won, E.
name: Yamaoka, J.
name: Yashchenko, S.
name: Yook, Y.
name: Yuan, C. Z.
name: Zhang, Z. P.
name: Zhilich, V.
name: Zhulanov, V.
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: Using data samples of $102\times10^6$ $Υ(1S)$ and $158\times10^6$ $Υ(2S)$ events collected with the Belle detector, a first experimental search has been made for double-charmonium production in the exclusive decays $Υ(1S,2S)\rightarrow J/ψ(ψ')+X$, where $X=η_c$, $χ_{cJ} (J=~0,~1,~2)$, $η_c(2S)$, $X(3940)$, and $X(4160)$. No significant signal is observed in the spectra of the mass recoiling against the reconstructed $J/ψ$ or $ψ'$ except for the evidence of $χ_{c1}$ production with a significance of $4.6σ$ for $Υ(1S)\rightarrow J/ψ+χ_{c1}$. The measured branching fraction $\BR(Υ(1S)\rightarrow J/ψ+χ_{c1})$ is $(3.90\pm1.21(\rm stat.)\pm0.23 (\rm syst.))\times10^{-6}$. The $90\%$ confidence level upper limits on the branching fractions of the other modes having a significance of less than $3σ$ are determined. These results are consistent with theoretical calculations using the nonrelativistic QCD factorization approach.
description: 12 pages, 4 figures, 1 table. The fit range was extended to include X(4160) signal according to referee's suggestions. Other results unchanged. Paper was accepted for publication as a regular article in Physical Review D