Dergi makalesi Açık Erişim

Study of the decays ${\chi }_{cJ}\to \Lambda \overline{\Lambda }\varphi $

2024    CERN İşbirliği

Based on $\left(2712.4±14.3\right)×{10}^{6}$ ${e}^{+}{e}^{-}\to \psi \left(3686\right)$ events collected with the BESIII detector operating at the BEPCII Collider, we report the first evidence of ${\chi }_{c0}\to \Lambda \overline{\Lambda }\varphi $ decays and the first observation of ${\chi }_{c1,2}\to \Lambda \overline{\Lambda }\varphi $ decays, with significances of $4.1\sigma $, $11.3\sigma $ and $13.0\sigma $, respectively. The decay branching fractions of ${\chi }_{c0,1,2}\to \Lambda \overline{\Lambda }\varphi $ are measured to be $\left(2.99±1.24±0.19\right)×{10}^{-5}$, $\left(6.01±0.90±0.40\right)×{10}^{-5}$, and $\left(7.13±0.81±0.36\right)×{10}^{-5}$, where the first uncertainties are statistical and the second systematic. No obvious enhancement near the $\Lambda \overline{\Lambda }$ production threshold or excited $\Lambda $ state is found in the $\Lambda \varphi $ (or $\overline{\Lambda }\varphi $) system.