Evidence for a vector charmoniumlike state in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msup><mml:mi>e</mml:mi><mml:mo>+</mml:mo></mml:msup><mml:msup><mml:mi>e</mml:mi><mml:mo>−</mml:mo></mml:msup><mml:mo stretchy="false">→</mml:mo><mml:msubsup><mml:mi>D</mml:mi><mml:mi>s</mml:mi><mml:mo>+</mml:mo></mml:msubsup><mml:msubsup><mml:mi>D</mml:mi><mml:mrow><mml:mi>s</mml:mi><mml:mn>2</mml:mn></mml:mrow><mml:mo>*</mml:mo></mml:msubsup><mml:mo stretchy="false">(</mml:mo><mml:mn>2573</mml:mn><mml:msup><mml:mo stretchy="false">)</mml:mo><mml:mo>−</mml:mo></mml:msup><mml:mo>+</mml:mo><mml:mi mathvariant="normal">c</mml:mi><mml:mo>.</mml:mo><mml:mi mathvariant="normal">c</mml:mi><mml:mo>.</mml:mo></mml:math>
S. Jia, C. P. Shen, I. Adachi, H. Aihara, S. Al Said, D. M. Asner, H. Atmacan, V. Aulchenko, T. Aushev, R. Ayad, I. Badhrees, P. K. Behera, K. Belous, J. V. Bennett, D. Besson, V. Bhardwaj, T. Bilka, J. P. Biswal, G. Bonvicini, A. Bożek, M. Bračko, T. E. Browder, M. Campajola, D. Červenkov, P. Chang, A. Chen, B. G. Cheon, K. Chilikin, K. Cho, S. K. Choi, Y. Choi, S. Choudhury, D. Cinabro, S. Cunliffe, N. Dash, G. De Nardo, F. Di Capua, Z. Doležal, T. V. Dong, S. Eidelman, D. Epifanov, J. E. Fast, T. Ferber, D. Ferlewicz, B. G. Fulsom, R. B. Garg, V. Gaur, N. Gabyshev, A. Garmash, A. Giri, P. Goldenzweig, B. Golob, O. Grzymkowska, O. Hartbrich, K. Hayasaka, H. Hayashii, W.-S. Hou, C.-L. Hsu, K. Inami, G. Inguglia, A. Ishikawa, R. Itoh, M. Iwasaki, M. Iwasaki, H. B. Jeon, Yaochu Jin, K. K. Joo, G. Karyan, T. Kawasaki, C. Kiesling, B. H. Kim, D. Y. Kim, K.-H. Kim, S. H. Kim, Y.-K. Kim, K. Kinoshita, P. Kodyš, S. Korpar, D. Kotchetkov, P. Križan, R. Kroeger, P. Krokovny, R. Kulasiri, A. Kuzmin, Y.-J. Kwon, K. Lalwani, J. S. Lange, S. C. Lee, L. K. Li, Y. B. Li, L. Li Gioi, J. Libby, K. Lieret, D. Liventsev, J. MacNaughton, C. MacQueen, M. Masuda, T. Matsuda, D. Matvienko, M. Merola
Abstract
We report the measurement of ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{D}_{s}^{+}{D}_{s2}^{*}(2573{)}^{\ensuremath{-}}+\mathrm{c}.\mathrm{c}.$ via initial-state radiation using a data sample of an integrated luminosity of $921.9\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ collected with the Belle detector at the $\mathrm{\ensuremath{\Upsilon}}(4S)$ and nearby. We find evidence for an enhancement with a $3.4\ensuremath{\sigma}$ significance in the invariant mass of ${D}_{s}^{+}{D}_{s2}^{*}(2573{)}^{\ensuremath{-}}+\mathrm{c}.\mathrm{c}.$ The measured mass and width are $({4619.8}_{\ensuremath{-}8.0}^{+8.9}(\mathrm{stat}.)\ifmmode\pm\else\textpm\fi{}2.3(\mathrm{syst}.))\text{ }\text{ }\mathrm{MeV}/{c}^{2}$ and $({47.0}_{\ensuremath{-}14.8}^{+31.3}(\mathrm{stat}.)\ifmmode\pm\else\textpm\fi{}4.6(\mathrm{syst}.))\text{ }\text{ }\mathrm{MeV}$, respectively. The mass, width, and quantum numbers of this enhancement are consistent with the charmoniumlike state at $4626\text{ }\text{ }\mathrm{MeV}/{c}^{2}$ recently reported by Belle in ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{D}_{s}^{+}{D}_{s1}(2536{)}^{\ensuremath{-}}+\mathrm{c}.\mathrm{c}.$ The product of the ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{D}_{s}^{+}{D}_{s2}^{*}(2573{)}^{\ensuremath{-}}+\mathrm{c}.\mathrm{c}.$ cross section and the branching fraction of ${D}_{s2}^{*}(2573{)}^{\ensuremath{-}}\ensuremath{\rightarrow}{\overline{D}}^{0}{K}^{\ensuremath{-}}$ is measured from ${D}_{s}^{+}{D}_{s2}^{*}(2573{)}^{\ensuremath{-}}$ threshold to 5.6 GeV.