Study of $e^+ e^- \to π^+ π^- J/ψ$ and Observation of a Charged Charmonium-like State at Belle
Creators: name: Belle Collaboration
name: Liu, Z. Q.
name: Shen, C. P.
name: Yuan, C. Z.
name: Adachi, I.
name: Aihara, H.
name: Asner, D. M.
name: Aulchenko, V.
name: Aushev, T.
name: Aziz, T.
name: Bakich, A. M.
name: Bala, A.
name: Belous, K.
name: Bhuyan, B.
name: Bischofberger, M.
name: Bondar, A.
name: Bonvicini, G.
name: Bozek, A.
name: Bračko, M.
name: Brodzicka, J.
name: Browder, T. E.
name: Chang, P.
name: Chekelian, V.
name: Chen, A.
name: Chen, P.
name: Cheon, B. G.
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: Doležal, Z.
name: Drásal, Z.
name: Drutskoy, A.
name: Dutta, D.
name: Dutta, K.
name: Eidelman, S.
name: Epifanov, D.
name: Farhat, H.
name: Fast, J. E.
name: Feindt, M.
name: Ferber, T.
name: Frey, A.
name: Gaur, V.
name: Gabyshev, N.
name: Ganguly, S.
name: Gillard, R.
name: Goh, Y. M.
name: Golob, B.
name: Haba, J.
name: Hayasaka, K.
name: Hayashii, H.
name: Horii, Y.
name: Hoshi, Y.
name: Hou, W. -S.
name: Hsiung, Y. B.
name: Hyun, H. J.
name: Iijima, T.
name: Inami, K.
name: Ishikawa, A.
name: Itoh, R.
name: Iwasaki, Y.
name: Joffe, D.
name: Julius, T.
name: Kah, D. H.
name: Kang, J. H.
name: Kawasaki, T.
name: Kiesling, C.
name: Kim, H. J.
name: Kim, J. B.
name: Kim, J. H.
name: Kim, K. T.
name: Kim, M. J.
name: Kim, Y. J.
name: Kinoshita, K.
name: Klucar, J.
name: Ko, B. R.
name: Kodyš, P.
name: Korpar, S.
name: Križan, P.
name: Krokovny, P.
name: Kuhr, T.
name: Kwon, Y. -J.
name: Lange, J. S.
name: Lee, S. -H.
name: Li, J.
name: Li, Y.
name: Libby, J.
name: Liu, C.
name: Lukin, P.
name: Matvienko, D.
name: Miyabayashi, K.
name: Miyata, H.
name: Mizuk, R.
name: Mohanty, G. B.
name: Moll, A.
name: Mussa, R.
name: Nakano, E.
name: Nakao, M.
name: Natkaniec, Z.
name: Nayak, M.
name: Nedelkovska, E.
name: Nisar, N. K.
name: Nishida, S.
name: Nitoh, O.
name: Ogawa, S.
name: Okuno, S.
name: Olsen, S. L.
name: Onuki, Y.
name: Ostrowicz, W.
name: Oswald, C.
name: Pakhlov, P.
name: Pakhlova, G.
name: Park, H.
name: Park, H. K.
name: Pestotnik, R.
name: Petrič, M.
name: Piilonen, L. E.
name: Ritter, M.
name: Röhrken, M.
name: Rostomyan, A.
name: Sahoo, H.
name: Saito, T.
name: Sakai, Y.
name: Sandilya, S.
name: Santel, D.
name: Sanuki, T.
name: Sato, Y.
name: Savinov, V.
name: Schneider, O.
name: Schnell, G.
name: Schwanda, C.
name: Seidl, R.
name: Semmler, D.
name: Senyo, K.
name: Seon, O.
name: Sevior, M. E.
name: Shapkin, M.
name: Shibata, T. -A.
name: Shiu, J. -G.
name: Shwartz, B.
name: Sibidanov, A.
name: Simon, F.
name: Smerkol, P.
name: Sohn, Y. -S.
name: Sokolov, A.
name: Solovieva, E.
name: Starič, M.
name: Steder, M.
name: Sumihama, M.
name: Sumiyoshi, T.
name: Tamponi, U.
name: Tanida, K.
name: Tatishvili, G.
name: Teramoto, Y.
name: Trabelsi, K.
name: Tsuboyama, T.
name: Uchida, M.
name: Uehara, S.
name: Uglov, T.
name: Unno, Y.
name: Uno, S.
name: Van Hulse, C.
name: Vanhoefer, P.
name: Varner, G.
name: Varvell, K. E.
name: Vorobyev, V.
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: Yabsley, B. D.
name: Yamaoka, J.
name: Yamashita, Y.
name: Yashchenko, S.
name: Yook, Y.
name: Yusa, Y.
name: Zhang, C. C.
name: Zhang, Z. P.
name: Zhilich, V.
name: Zupanc, A.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: The cross section for $e^+ e^- \to π^+ π^- J/ψ$ between 3.8 GeV and 5.5 GeV is measured with a 967 fb$^{-1}$ data sample collected by the Belle detector at or near the $Υ(nS)$ ($n = 1,\ 2,\ ...,\ 5$) resonances. The Y(4260) state is observed, and its resonance parameters are determined. In addition, an excess of $π^+ π^- J/ψ$ production around 4 GeV is observed. This feature can be described by a Breit-Wigner parameterization with properties that are consistent with the Y(4008) state that was previously reported by Belle. In a study of $Y(4260) \to π^+ π^- J/ψ$ decays, a structure is observed in the $M(π^\pm\jpsi)$ mass spectrum with $5.2σ$ significance, with mass $M=(3894.5\pm 6.6\pm 4.5) {\rm MeV}/c^2$ and width $Γ=(63\pm 24\pm 26)$ MeV/$c^{2}$, where the errors are statistical and systematic, respectively. This structure can be interpreted as a new charged charmonium-like state.
description: 10 pages, 5 figures, 2 tables, accepted by Phys. Rev. Lett