Search for new hadronic decays of hc and observation of hc → pp¯η.

A search for the hadronic decays of the h_c meson to the final states p p ¯ π⁺π⁻π⁰, p p ¯ η , and p p ¯ π⁰ via the process ψ(3686) → π⁰h_c is performed using (4.48 ± 0.03) × 10⁸ψ(3686) events collected with the BESIII detector. The decay channel h_c → p p ¯ η is observed for the first time with a significance greater than 5σ and a branching fraction of (6.41 ± 1.74 ± 0.53 ± 1.00) × 10⁻⁴, where the uncertainties are statistical, systematic, and that from the branching fraction of ψ(3686) → π⁰h_c. Strong evidence for the decay h_c → p p ¯ π⁺π⁻π⁰ is found with a significance of 4.9σ and a branching fraction of (3.84 ± 0.83 ± 0.69 ± 0.58) × 10⁻³. The significances include systematic uncertainties. No clear signal of the decay h_c → p p ¯ π⁰ is found, and an upper limit of 6.59 × 10⁻⁴ on its branching fraction is set at the 90% confidence level. [ABSTRACT FROM AUTHOR]