First observations of hc →hadrons

Abstract

Based on (4.48±0.03)×108 ψ(3686) events, collected with the BESIII detector at the BEPCII storage ring, five hc hadronic decays are searched for via the process ψ(3686)→π0hc. Three of them, hc→ppπ+π-, π+π-π0, and 2(π+π-)π0, are observed for the first time with significances of 7.4σ, 4.6σ, and 9.1σ, and their branching fractions are determined to be (2.89±0.32±0.55)×10-3, (1.60±0.40±0.32)×10-3, and (7.44±0.94±1.52)×10-3, respectively, where the first uncertainties are statistical and the second systematic. No significant signal is observed for the other two decay modes, and the corresponding upper limits of the branching fractions are determined to be B(hc→3(π+π-)π0)<8.7×10-3 and B(hc→K+K-π+π-)<5.8×10-4 at the 90% confidence level.