First observation of the η c → Ξ 0 Ξ ¯ 0 decay

Physical review. D/Physical review. D. 2026 Open access

Read full text
Authors: M. Ablikim, Mikhail N. Achasov, P. Adlarson, X. Ai, C. S. Akondi, R. Aliberti, A. Amoroso, Q. An, Q. An, Y. H. An, Olga Bakina, Y. Ban
+88 more H. -R. Bao, X. L. Bao, V. Batozskaya, K. Begzsuren, Niklaus Berger, M. Berlowski, M. B. Bertani, D. Bettoni, Fabrizio Bianchi, E. Bianco, A. Bortone, I. Boyko, Roy A. Briere, A. Brueggemann, H. Cai, H. Cai, M. H. Cai, Alessandro Calcaterra, G. F. Cao, G. F. Cao, Serkant Ali Cetin, X. Y. Chai, J. F. Chang, J. F. Chang, G. R. Che, G. R. Che, Y. Z. Che, C. H. Chen, G. Chen, G. Chen, H. Y. Chen, H. Y. Chen, M. L. Chen, S. J. Chen, S. J. Chen, T. Chen, W. Chen, X. T. Chen, X. T. Chen, X. T. Chen, Y. B. Chen, Y. B. Chen, Z. K. Chen, J. Cheng, S.-K. Choi, X. Chu, G. Cibinetto, F. Cossio, J. Cottee Meldrum, H. L. Dai, H. L. Dai, J. P. Dai, A. Dbeyssi, R. E. de Boer, D. Dedovich, C. Q. Deng, C. Q. Deng, Z. Y. Deng, I. Denisenko, Marco Giovanni Maria Destefanis, F. De Mori, J. Dong, X. X. Ding, Y. X. Ding, Y. X. Ding, Yi. Ding, L. Y. Dong, L. Y. Dong, M. Y. Dong, M. C. Du, S. X. Du, M. C. Du, S. X. Du, Shaoxu Du, X. L. Du, Y. Q. Du, P. Egorov, Gaofeng Fan, J. J. Fan, G. F. Fan, J. J. Fan, Y. H. Fan, Jin Fang, J. Fang, S. S. Fang, L. Fava, F. Feldbauer, Giulietto Felici
DOI: 10.1103/ckyx-hyjm
Cited by: 0
References: 41

Abstract

Using ( 10087 ± 44 ) × 10 6 J / ψ events collected with the BESIII detector at the BEPCII collider, we report the first observation of the decay η c → Ξ 0 Ξ ¯ 0 . The interference between J / ψ → γ η c → γ Ξ 0 Ξ ¯ 0 and J / ψ → γ Ξ 0 Ξ ¯ 0 | non − resonance is considered in the Ξ 0 Ξ ¯ 0 mass spectrum fits. The branching fractions are measured to be B ( η c → Ξ 0 Ξ ¯ 0 ) = ( 1.33 ± 0.03 ± 0.18 ) × 10 − 3 for the constructive interference and B ( η c → Ξ 0 Ξ ¯ 0 ) = ( 1.63 ± 0.04 ± 0.21 ) × 10 − 3 for the destructive interference, where the first uncertainties are statistical and the second are systematic.

Fields of Study & Subjects

Quantum Chromodynamics and Particle Interactions Particle physics theoretical and experimental studies High-Energy Particle Collisions Research

Publication details

Journal / source
Physical review. D/Physical review. D.
Volume
113
Issue
7
Publication date
17 March 2026
Language
EN