Measurement of branching fractions of J/ψ and ψ(3686) decays to Σ+ and $$ \overline{\Sigma} $$−

Abstract

Using 1310.6 × 106J/ψ and 448.1 × 106ψ(3686) events collected with the BESIII detector, the branching fractions of J/ψ decays to Σ+$$ \overline{\Sigma} $$ Σ ¯ − is measured to be (10.61 ± 0.04 ± 0.36) × 10−4, which is significantly more precise than the current world average. The branching fractions of ψ(3686) decays to Σ+$$ \overline{\Sigma} $$ Σ ¯ − is measured to be (2.52 ± 0.04 ± 0.09) × 10−4, which is consistent with the previous measurements. In addition, the ratio of $$ \mathcal{B} $$ B (ψ(3686) → Σ+$$ \overline{\Sigma} $$ Σ ¯ −)/$$ \mathcal{B} $$ B (J/ψ → Σ+$$ \overline{\Sigma} $$ Σ ¯ −) is determined to be (23.8 ± 1.1)% which violates the “12% rule”.