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新山 雅之 所属 京都産業大学 理学部 物理科学科 職種 教授 |
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| 発行・発表の年月 | 2022/08 |
| 形態種別 | その他 |
| 標題 | Measurement of two-photon decay width of $χ_{c2}(1P)$ in $ γ γ\rightarrow χ_{c2}(1P) \rightarrow J/ψγ$ at Belle |
| 執筆形態 | その他 |
| 著者・共著者 | The Belle Collaboration,Y. Seino,K. Hayasaka,S. Uehara,I. Adachi,H. Aihara,S. Al Said,D. M. Asner,H. Atmacan,T. Aushev,R. Ayad,V. Babu,S. Bahinipati,P. Behera,K. Belous,J. Bennett,M. Bessner,V. Bhardwaj,B. Bhuyan,T. Bilka,D. Bodrov,G. Bonvicini,J. Borah,A. Bozek,M. Bračko,P. Branchini,T. E. Browder,A. Budano,M. Campajola,D. Červenkov,M. -C. Chang,P. Chang,V. Chekelian,A. Chen,B. G. Cheon,K. Chilikin,H. E. Cho,K. Cho,S. -J. Cho,S. -K. Choi,Y. Choi,S. Choudhury,D. Cinabro,S. Das,G. De Pietro,R. Dh |
| 概要 | We report the measurement of the two-photon decay width of $\chi_{c2}(1P)$ in
two-photon processes at the Belle experiment. We analyze the process $ \gamma \gamma \rightarrow \chi_{c2}(1P) \rightarrow J/\psi\gamma$, $J/\psi \rightarrow \ell^{+} \ell^{-}$ $(\ell = e \ {\rm or} \ \mu)$ using a data sample of 971 fb$^{-1}$ collected with the Belle detector at the KEKB $e^{+} e^{-}$ collider. In this analysis, the product of the two-photon decay width of $\chi_{c2}(1P)$ and the branching fraction is determined to be $\Gamma_{\gamma \gamma}(\chi_{c2}(1P)) \mathcal{B}( \chi_{c2}(1P) \rightarrow J/\psi \, \gamma )\mathcal{B}( J/\psi \rightarrow \ell^+\ell^- ) = {\rm 14.8}$ $\pm$ ${\rm 0.3}({\rm stat.})$ $\pm$ ${\rm 0.7}({\rm syst.})$ eV, which corresponds to $ \Gamma_{\gamma \gamma}(\chi_{c2}(1P)) $ = 653 $\pm$ 13(stat.) $\pm$ 31(syst.) $\pm$ 17(B.R.) eV, where the third uncertainty is from $\mathcal{B}( \chi_{c2}(1P) \rightarrow J/\psi \, \gamma )$ and $\mathcal{B}( J/\psi \rightarrow \ell^+\ell^- )$. |
| PermalinkURL | http://arxiv.org/abs/2208.04477v4 |
| researchmap用URL | http://arxiv.org/pdf/2208.04477v4 |