Study of Open-Charm Decays and Radiative Transitions of the <i>X</i>(3872)
M. Ablikim, М. Н. Ачасов, P. Adlarson, S. Ahmed, M. Albrecht, A. Amoroso, Q. An, Anita, Y. Bai, O. Bakina, R. Baldini Ferroli, I. Balossino, Y. Ban, K. Begzsuren, J. V. Bennett, N. Berger, M. Bertani, D. Bettoni, F. Bianchi, J. Biernat, J. Bloms, A. Bortone, I. Boyko, R. A. Briere, H. Cai, X. Cai, A. Calcaterra, G. F. Cao, N. Cao, S. A. Çetin, J. F. Chang, W. L. Chang, G. Chelkov, D. Y. Chen, G. Chen, H. S. Chen, M. L. Chen, S. J. Chen, X. R. Chen, Y. B. Chen, W. Cheng, G. Cibinetto, F. Cossio, X. F. Cui, H. L. Dai, J. P. Dai, X. C. Dai, A. Dbeyssi, R. B. de Boer, D. Dedovich, Z. Y. Deng, A. Denig, I. Denysenko, M. Destefanis, F. De Mori, Y. Ding, C. Dong, J. Dong, L. Y. Dong, M. Y. Dong, S. X. Du, J. Fang, S. S. Fang, Y. Fang, R. Farinelli, L. Fava, F. Feldbauer, G. Felici, C. Q. Feng, M. Fritsch, C. D. Fu, Y. Fu, X. L. Gao, Y. Gao, Y. Gao, Y. Gao, I. Garzia, E. M. Gersabeck, A. Gilman, K. Goetzen, L. Gong, W. X. Gong, W. Gradl, M. Greco, L. M. Gu, M. H. Gu, S. Gu, Y. T. Gu, C. Y. Guan, A. Q. Guo, L. B. Guo, R. P. Guo, Y. P. Guo, A. Guskov, S. Han, T. T. Han, T. Z. Han, X. Q. Hao, F. A. Harris, K. L. He
Abstract
The processes $X(3872)\ensuremath{\rightarrow}{D}^{*0}{\overline{D}}^{0}+\mathrm{c}.\mathrm{c}.,\ensuremath{\gamma}J/\ensuremath{\psi},\ensuremath{\gamma}\ensuremath{\psi}(2S)$, and $\ensuremath{\gamma}{D}^{+}{D}^{\ensuremath{-}}$ are searched for in a $9.0\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data sample collected at center-of-mass energies between 4.178 and 4.278 GeV with the BESIII detector. We observe $X(3872)\ensuremath{\rightarrow}{D}^{*0}\overline{{D}^{0}}+\mathrm{c}.\mathrm{c}.$ and find evidence for $X(3872)\ensuremath{\rightarrow}\ensuremath{\gamma}J/\ensuremath{\psi}$ with statistical significances of $7.4\ensuremath{\sigma}$ and $3.5\ensuremath{\sigma}$, respectively. No evident signals for $X(3872)\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\psi}(2S)$ and $\ensuremath{\gamma}{D}^{+}{D}^{\ensuremath{-}}$ are found, and the upper limit on the relative branching ratio ${R}_{\ensuremath{\gamma}\ensuremath{\psi}}\ensuremath{\equiv}{\mathcal{B}[X(3872)\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\psi}(2S)]}/{\mathcal{B}[X(3872)\ensuremath{\rightarrow}\ensuremath{\gamma}J/\ensuremath{\psi}]}<0.59$ is set at 90% confidence level. Measurements of branching ratios relative to decay $X(3872)\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}J/\ensuremath{\psi}$ are also reported for decays $X(3872)\ensuremath{\rightarrow}{D}^{*0}\overline{{D}^{0}}+\mathrm{c}.\mathrm{c}.,\ensuremath{\gamma}\ensuremath{\psi}(2S),\ensuremath{\gamma}J/\ensuremath{\psi}$, and $\ensuremath{\gamma}{D}^{+}{D}^{\ensuremath{-}}$, as well as the non-${D}^{*0}\overline{{D}^{0}}$ three-body decays ${\ensuremath{\pi}}^{0}{D}^{0}\overline{{D}^{0}}$ and $\ensuremath{\gamma}{D}^{0}\overline{{D}^{0}}$.