Çetin, Serkant Ali2021-06-032021-06-032019-06-272470-0010https://hdl.handle.net/11411/3684https://doi.org/10.1103/PhysRevD.99.112010Using a data sample of 4.48×108 ?(3686) events collected with the BESIII detector, we present a first observation of ?(3686)?pp ?, and we measure its branching fraction to be [6.06±0.38(stat)±0.48(syst)]×10-6. In contrast to the earlier discovery of a threshold enhancement in the pp-mass spectrum of the channel J/???pp, denoted as X(pp), we do not find a similar enhancement in ?(3686)?pp?. An upper limit of 1.82×10-7 at the 90% confidence level on the branching fraction of ?(3686)?X(pp)??pp? is obtained.eninfo:eu-repo/semantics/openAccessArticle2-s2.0-8507143193510.1103/PhysRevD.99.112010Q1WOS:000473026500002