Observation of ${\chi }_{cJ}\to 3\left({K}^{+}{K}^{-}\right)$

By analyzing $\left(27.12±0.14\right)×{10}^{8}\text{}\text{}\psi \left(3686\right)$ events collected with the BESIII detector operating at the BEPCII collider, the decay processes ${\chi }_{cJ}\to 3\left({K}^{+}{K}^{-}\right)$ ($J=0$, 1, 2) are observed for the first time with statistical significances of $8.2\sigma $, $8.1\sigma $, and $12.4\sigma $, respectively. The product branching fractions of $\psi \left(3686\right)\to \gamma {\chi }_{cJ}$, ${\chi }_{cJ}\to 3\left({K}^{+}{K}^{-}\right)$ are presented and the branching fractions of ${\chi }_{cJ}\to 3\left({K}^{+}{K}^{-}\right)$ decays are determined to be ${B}_{{\chi }_{c0}\to 3\left({K}^{+}{K}^{-}\right)}=\left(10.7±1.8±1.1\right)×{10}^{-6}$, ${B}_{{\chi }_{c1}\to 3\left({K}^{+}{K}^{-}\right)}=\left(4.2±0.9±0.5\right)×{10}^{-6}$, and ${B}_{{\chi }_{c2}\to 3\left({K}^{+}{K}^{-}\right)}=\left(7.2±1.1±0.8\right)×{10}^{-6}$, where the first uncertainties are statistical and the second are systematic.