Search for new hadronic decays of hc and observation of hc ?K+K-?+?-?0

Abstract

Ten hadronic final states of the hc decays are investigated via the process ?(3686)??0hc, using a data sample of (448.1±2.9)×106 ?(3686) events collected with the BESIII detector. The decay channel hc?K+K-?+?-?0 is observed for the first time and has a measured significance of 6.0?. The corresponding branching fraction is determined to be B(hc?K+K-?+?-?0)=(3.3±0.6±0.6)×10-3 (where the uncertainties are statistical and systematic, respectively). Evidence for the decays hc??+?-?0? and hc?KS0K±???+?- is found with a significance of 3.6? and 3.8?, respectively. The corresponding branching fractions (and upper limits) are obtained to be B(hc??+?-?0?)=(7.2±1.8±1.3)×10-3 (<1.8×10-2) and B(hc?KS0K±???+?-)=(2.8±0.9±0.5)×10-3 (<4.7×10-3). Upper limits on the branching fractions for the final states hc?K+K-?0, K+K-?, K+K-?+?-?, 2(K+K-)?0, K+K-?0?, KS0K±??, and pp¯?0?0 are determined at a confidence level of 90%. © 2020 authors. Published by the American Physical Society.