Measurements of the branching fractions of Ξ c 0 → Ξ 0 π 0 $$ {\Xi}_c^0\to {\Xi}^0{\pi}^0 $$ , Ξ c 0 → Ξ 0 η $$ {\Xi}_c^0\to {\Xi}^0\eta $$ , and Ξ c 0 → Ξ 0 η ′ $$ {\Xi}_c^0\to {\Xi}^0{\eta}^{\prime } $$ and asymmetry parameter of Ξ c 0 → Ξ 0 π 0 $$ {\Xi}_c^0\to {\Xi}^0{\pi}^0

• Published in: The journal of high energy physics 2024-10, Vol.2024 (10), p.1-24
• Main Authors: The Belle and Belle II collaboration, I. Adachi, L. Aggarwal, H. Aihara, N. Akopov, A. Aloisio, N. Althubiti, N. Anh Ky, D. M. Asner, H. Atmacan, T. Aushev, V. Aushev, M. Aversano, R. Ayad, V. Babu, H. Bae, S. Bahinipati, P. Bambade, Sw. Banerjee, M. Barrett, J. Baudot, A. Baur, A. Beaubien, F. Becherer, J. Becker, J. V. Bennett, F. U. Bernlochner, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, B. Bhuyan, F. Bianchi, L. Bierwirth, T. Bilka, D. Biswas, A. Bobrov, D. Bodrov, J. Borah, A. Boschetti, A. Bozek, M. Bračko, P. Branchini, T. E. Browder, A. Budano, S. Bussino, Q. Campagna, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, J. Cerasoli, M.-C. Chang, P. Chang, P. Cheema, C. Chen, B. G. Cheon, K. Chilikin, K. Chirapatpimol, H.-E. Cho, K. Cho, S.-J. Cho, S.-K. Choi, S. Choudhury, L. Corona, J. X. Cui, F. Dattola, E. De La Cruz-Burelo, S. A. De La Motte, G. De Nardo, G. De Pietro, R. de Sangro, M. Destefanis, S. Dey, R. Dhamija, A. Di Canto, F. Di Capua, J. Dingfelder, Z. Doležal, I. Domínguez Jiménez, T. V. Dong, M. Dorigo, K. Dort, D. Dossett, S. Dubey, K. Dugic, G. Dujany, P. Ecker, M. Eliachevitch, D. Epifanov, P. Feichtinger, T. Ferber, T. Fillinger, C. Finck, A. Fodor, F. Forti, A. Frey, B. G. Fulsom, A. Gabrielli
• Format: Article
• Language: English
• Subjects: Branching fraction; Charm Physics; e +-e − Experiments; Particle and Resonance Production
• ISSN: 1029-8479
• DOI: 10.1007/JHEP10(2024)045

Abstract We present a study of Ξ c 0 → Ξ 0 π 0 $$ {\Xi}_c^0\to {\Xi}^0{\pi}^0 $$ , Ξ c 0 → Ξ 0 η $$ {\Xi}_c^0\to {\Xi}^0\eta $$ , and Ξ c 0 → Ξ 0 η ′ $$ {\Xi}_c^0\to {\Xi}^0{\eta}^{\prime } $$ decays using the Belle and Belle II data samples, which have integrated luminosities of 980 fb −1 and 426 fb −1, respectively. We measure the following relative branching fractions B Ξ c 0 → Ξ 0 π 0 / B Ξ c 0 → Ξ − π + = 0.48 ± 0.02 stat ± 0.03 syst , B Ξ c 0 → Ξ 0 η / B Ξ c 0 → Ξ − π + = 0.11 ± 0.01 stat ± 0.01 syst , B Ξ c 0 → Ξ 0 η ′ / B Ξ c 0 → Ξ − π + = 0.08 ± 0.02 stat ± 0.01 syst $$ {\displaystyle \begin{array}{c}\mathcal{B}\left({\Xi}_c^0\to {\Xi}^0{\pi}^0\right)/\mathcal{B}\left({\Xi}_c^0\to {\Xi}^{-}{\pi}^{+}\right)=0.48\pm 0.02\left(\textrm{stat}\right)\pm 0.03\left(\textrm{syst}\right),\\ {}\mathcal{B}\left({\Xi}_c^0\to {\Xi}^0\eta \right)/\mathcal{B}\left({\Xi}_c^0\to {\Xi}^{-}{\pi}^{+}\right)=0.11\pm 0.01\left(\textrm{stat}\right)\pm 0.01\left(\textrm{syst}\right),\\ {}\mathcal{B}\left({\Xi}_c^0\to {\Xi}^0{\eta}^{\prime}\right)/\mathcal{B}\left({\Xi}_c^0\to {\Xi}^{-}{\pi}^{+}\right)=0.08\pm 0.02\left(\textrm{stat}\right)\pm 0.01\left(\textrm{syst}\right)\end{array}} $$ for the first time, where the uncertainties are statistical (stat) and systematic (syst). By multiplying by the branching fraction of the normalization mode, B Ξ c 0 → Ξ − π + $$ \mathcal{B}\left({\Xi}_c^0\to {\Xi}^{-}{\pi}^{+}\right) $$ , we obtain the following absolute branching fraction results B Ξ c 0 → Ξ 0 π 0 = 6.9 ± 0.3 stat ± 0.5 syst ± 1.3 norm × 10 − 3 , B Ξ c 0 → Ξ 0 η = 1.6 ± 0.2 stat ± 0.2 syst ± 0.3 norm × 10 − 3 , B Ξ c 0 → Ξ 0 η ′ = 1.2 ± 0.3 stat ± 0.1 syst ± 0.2 norm × 10 − 3 , $$ {\displaystyle \begin{array}{c}\mathcal{B}\left({\Xi}_c^0\to {\Xi}^0{\pi}^0\right)=\left(6.9\pm 0.3\left(\textrm{stat}\right)\pm 0.5\left(\textrm{syst}\right)\pm 1.3\left(\operatorname{norm}\right)\right)\times {10}^{-3},\\ {}\mathcal{B}\left({\Xi}_c^0\to {\Xi}^0\eta \right)=\left(1.6\pm 0.2\left(\textrm{stat}\right)\pm 0.2\left(\textrm{syst}\right)\pm 0.3\left(\operatorname{norm}\right)\right)\times {10}^{-3},\\ {}\mathcal{B}\left({\varXi}_c^0\to {\Xi}^0{\eta}^{\prime}\right)=\left(1.2\pm 0.3\left(\textrm{stat}\right)\pm 0.1\left(\textrm{syst}\right)\pm 0.2\left(\operatorname{norm}\right)\right)\times {10}^{-3},\end{array}} $$ where the third uncertainties are from B Ξ c 0 → Ξ − π + $$ \mathcal{B}\left({\Xi}_c^0\to {\Xi}^{-}{\pi}^{+}\right) $$ . The asymmetry parameter for Ξ c 0 → Ξ 0 π 0 $$