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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 | 2023/08 |
| 形態種別 | その他 |
| 標題 | Observation of charmed strange meson pair production in $Υ(2S)$ decays and in $e^{+}e^{-}$ annihilation at $\sqrt{s} = 10.52~ \rm{GeV}$ |
| 執筆形態 | その他 |
| 著者・共著者 | Belle Collaboration,B. S. Gao,W. J. Zhu,X. L. Wang,I. Adachi,H. Aihara,D. M. Asner,V. Aulchenko,T. Aushev,R. Ayad,V. Babu,Sw. Banerjee,M. Bauer,P. Behera,K. Belous,J. Bennett,M. Bessner,V. Bhardwaj,T. Bilka,D. Biswas,A. Bobrov,D. Bodrov,A. Bondar,A. Bozek,M. Bračko,P. Branchini,T. E. Browder,A. Budano,D. Červenkov,M. -C. Chang,P. Chang,V. Chekelian,B. G. Cheon,K. Chilikin,H. E. Cho,K. Cho,S. -K. Choi,Y. Choi,S. Choudhury,D. Cinabro,G. De Nardo,G. De Pietro,R. Dhamija,F. Di Capua,J. Dingfelder,Z. |
| 概要 | We observe the process $\Upsilon(2S)\to D_s^{(*)+} D_{sJ}^{-}$ and continuum
production $e^+e^- \to D_s^{(*)+} D_{sJ}^- $ at $\sqrt{s} = 10.52$ GeV (and their charge conjugates) using the data samples collected by the Belle detector at KEKB, where $D_{sJ}^-$ is $D_{s1}(2536)^-$ or $D^{*}_{s2}(2573)^-$. Both $D_{sJ}^-$ states are identified through their decay into $\bar{K}\bar{D}^{(*)}$. We measure the products of branching fractions ${\cal B}(\Upsilon(2S) \to D_{s}^{(*)+} D_{sJ}^-) {\cal B}(D_{sJ}^-\to \bar{K} \bar{D}^{(*)})$ and the Born cross sections $\sigma^{\rm Born}(e^+e^- \to D_{s}^{(*)+} D_{sJ}^-) {\cal B}(D_{sJ}^-\to \bar{K} \bar{D}^{(*)})$, and then compare the ratios $R_1 \equiv {\cal B}(\Upsilon(2S)\to D_{s}^{(*)+} D_{sJ}^-)/{\cal B}(\Upsilon(2S)\to\mu^{+}\mu^-)$ for $\Upsilon(2S)$ decays and $R_2 \equiv \sigma^{\rm Born}(e^+e^-\to D_{s}^{(*)+}D_{sJ}^-)/\sigma^{\rm Born}(e^+e^-\to \mu^{+}\mu^-)$ for continuum production. We obtain $R_1/R_2 = 9.7\pm 2.3 \pm 1.1$, $6.8 \pm 2.1 \pm 0.8$, $10.2 \pm 3.3 \pm 2.5$, and $3.4 \pm 2.1 \pm 0.5$ for the $D_s^+ D_{s1}(2536)^-$, $D_s^{*+} D_{s1}(2536)^-$, $D_s^+ D_{s2}^{*}(2573)^{-}$, and $D_s^{*+} D_{s2}^{*}(2573)^{-}$ final states in the $D_{sJ}^-\to K^{-} \bar{D}^{(*)0}$ modes, respectively. Therefore, the strong decay is expected to dominate in the $\Upsilon(2S)\to D_{s}^{(*)+}D_{sJ}^-$ processes. We also measure the ratios of branching fractions ${\cal B}(D_{s1}(2536)^-\to K_S^0 D^{*}(2010)^{-})/{\cal B}(D_{s1}(2536)^-\to K^{-} D^{*}(2007)^0) = 0.48 \pm 0.07 \pm 0.02$ and ${\cal B}(D_{s2}^{*}(2573)^- \to K_S^0 D^-)/{\cal B}(D_{s2}^{*}(2573)^- \to K^{-}D^0) = 0.49 \pm 0.10 \pm 0.02$, which are consistent with isospin symmetry. The second ratio is the first measurement of this quantity. Here, the first uncertainties are statistical and the second are systematic. |
| PermalinkURL | http://arxiv.org/abs/2308.08900v3 |
| researchmap用URL | http://arxiv.org/pdf/2308.08900v3 |