Observation of X_cJ →3( K<SUP>+</SUP> K<SUP>-</SUP> )

By analyzing (27.12 +/- 0.14) x 10(8) Psi(3686) events collected with the BESIII detector operating at the BEPCII collider, the decay processes X-cJ -> 3( K+ K- ) (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(3686) -> gamma X-cJ , X-cJ -> 3( K+ K- ) are presented and the branching fractions of X-cJ -> 3( K+ K- ) decays are determined to be B-Xc0 -> 3( K+ K- ) = (10.7 +/- 1.8 +/- 1.1) x 10(-6), B-Xc1 -> 3( K+ K- ) = (4.2 +/- 0.9 +/- 0.5) x 10(-6), and B-Xc2 -> 3( K+ K- ) 1/4 (7.2 +/- 1.1 +/- 0.8) x 10(-6), where the first uncertainties are statistical and the second are systematic.