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arXiv · 2309.06368

Measurements of the absolute branching fractions of $\Omega^-$ decays and test of the $\Delta I = 1/2$ rule

BESIII Collaboration·M. Ablikim·M. N. Achasov·P. Adlarson·X. C. Ai·R. Aliberti·A. Amoroso·M. R. An·Q. An·Y. Bai·O. Bakina·I. Balossino·Y. Ban·V. Batozskaya·K. Begzsuren·N. Berger·M. Berlowski·M. Bertani·D. Bettoni·F. Bianchi·E. Bianco·A. Bortone·I. Boyko·R. A. Briere·A. Brueggemann·H. Cai·X. Cai·A. Calcaterra·G. F. Cao·N. Cao·S. A. Cetin·J. F. Chang·T. T. Chang·W. L. Chang·G. R. Che·G. Chelkov·C. Chen·Chao Chen·G. Chen·H. S. Chen·M. L. Chen·S. J. Chen·S. M. Chen·T. Chen·X. R. Chen·X. T. Chen·Y. B. Chen·Y. Q. Chen·Z. J. Chen·W. S. Cheng·S. K. Choi·X. Chu·G. Cibinetto·S. C. Coen·F. Cossio·J. J. Cui·H. L. Dai·J. P. Dai·A. Dbeyssi·R. E. de Boer·D. Dedovich·Z. Y. Deng·A. Denig·I. Denysenko·M. Destefanis·F. De Mori·B. Ding·X. X. Ding·Y. Ding·J. Dong·L. Y. Dong·M. Y. Dong·X. Dong·M. C. Du·S. X. Du·Z. H. Duan·P. Egorov·Y. H. Y. Fan·Y. L. Fan·J. Fang·S. S. Fang·W. X. Fang·Y. Fang·R. Farinelli·L. Fava·F. Feldbauer·G. Felici·C. Q. Feng·J. H. Feng·K Fischer·M. Fritsch·C. Fritzsch·C. D. Fu·J. L. Fu·Y. W. Fu·H. Gao·Y. N. Gao·Yang Gao·S. Garbolino·I. Garzia
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Abstract

Based on a data set of $(27.12\pm0.10)\times 10^8$ $\psi(3686)$ events collected at the BESIII experiment, the absolute branching fractions of the three dominant $\Omega^-$ decays are measured to be $\mathcal{B}_{\Omega^- \to \Xi^0 \pi^-} = (25.03\pm0.44\pm0.53)\%$, $\mathcal{B}_{\Omega^- \to \Xi^- \pi^0} = (8.43\pm0.52\pm0.28)\%$, and $\mathcal{B}_{\Omega^- \to \Lambda K^-} = (66.3\pm0.8\pm2.0)\%$, where the first and second uncertainties are statistical and systematic, respectively. The ratio between $\mathcal{B}_{\Omega^- \to \Xi^0 \pi^-}$ and $\mathcal{B}_{\Omega^- \to \Xi^- \pi^0}$ is determined to be $2.97\pm0.19\pm0.11$, which is in good agreement with the PDG value of $2.74\pm0.15$, but greater by more than four standard deviations than the theoretical prediction of 2 obtained from the $\Delta I = 1/2$ rule.

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BESIII Collaboration, M. Ablikim, M. N. Achasov, P. Adlarson, X. C. Ai, R. Aliberti, A. Amoroso, M. R. An, Q. An, Y. Bai, O. Bakina, I. Balossino, Y. Ban, V. Batozskaya, K. Begzsuren, N. Berger, M. Berlowski, M. Bertani, D. Bettoni, F. Bianchi, E. Bianco, A. Bortone, I. Boyko, R. A. Briere, A. Brueggemann, H. Cai, X. Cai, A. Calcaterra, G. F. Cao, N. Cao, S. A. Cetin, J. F. Chang, T. T. Chang, W. L. Chang, G. R. Che, G. Chelkov, C. Chen, Chao Chen, G. Chen, H. S. Chen, M. L. Chen, S. J. Chen, S. M. Chen, T. Chen, X. R. Chen, X. T. Chen, Y. B. Chen, Y. Q. Chen, Z. J. Chen, W. S. Cheng, S. K. Choi, X. Chu, G. Cibinetto, S. C. Coen, F. Cossio, J. J. Cui, H. L. Dai, J. P. Dai, A. Dbeyssi, R. E. de Boer, D. Dedovich, Z. Y. Deng, A. Denig, I. Denysenko, M. Destefanis, F. De Mori, B. Ding, X. X. Ding, Y. Ding, J. Dong, L. Y. Dong, M. Y. Dong, X. Dong, M. C. Du, S. X. Du, Z. H. Duan, P. Egorov, Y. H. Y. Fan, Y. L. Fan, J. Fang, S. S. Fang, W. X. Fang, Y. Fang, R. Farinelli, L. Fava, F. Feldbauer, G. Felici, C. Q. Feng, J. H. Feng, K Fischer, M. Fritsch, C. Fritzsch, C. D. Fu, J. L. Fu, Y. W. Fu, H. Gao, Y. N. Gao, Yang Gao, S. Garbolino, I. Garzia. 2023-09-12. Measurements of the absolute branching fractions of $\Omega^-$ decays and test of the $\Delta I = 1/2$ rule. https://doi.org/10.1103/physrevd.108.l091101

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