Observation of ψ(3686) → Ξ^- K⁰_S Ω⁺ +c.c

2025/04/06 by BESIII Collaboration, Ablikim, M., Achasov, M. N. +678
#FOS: Physical sciences #High Energy Physics - Experiment (hep-ex)

paper · doi:10.48550/arxiv.2504.04420

Abstract

Using a sample of (2.712±0.014) × 10⁹ ψ(3686) events collected with the BESIII detector at the electron positron collider BEPCII, the decay ψ(3686) → Ξ^- K⁰_S Ω⁺ +c.c. is observed for the first time, which has a significance of 5.9 standard deviations. The branching fraction of this decay is measured to be (2.91±0.47±0.33)× 10^-6, where the first and second uncertainties are statistical and systematic, respectively. The ratio between B_{ψ(3686) → Ξ^- K⁰S Ω⁺ +c.c.} and B_{ψ(3686) → Ω^- K⁺ Ξ⁰ +c.c.} is determined to be 1.05±0.23±0.14 , which deviates with the isospin symmetry conservation predicted value of 0.5 by 2.1σ.

Related

• Observation of ψ(3686) → Ω^- K⁺ Ξ⁰ +c.c
• Observation of ψ(3686) → K^-Λ(1520)Ξ⁺ + c.c.
• Observation of ψ(3686)→ 3ϕ
• Measurement of the Branching Fraction for the Decay ψ(3686) → ϕK_S⁰ K_S⁰
• Study of the decays ψ(3686)→γχ_cJ→γpK^*+Λ+c.c. and ψ(3686)→pK^*+Λ+c.c.