Observation of Cabibbo-Suppressed Two-Body Hadronic Decays and Precision Mass Measurement of the Ω⁰<i>_c</i> Baryon

The first observation of the singly Cabibbo-suppressed Ω0c→Ω−K+ and Ω0c→Ξ−π+ decays is reported, using proton-proton collision data at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.4  fb−1, collected with the LHCb detector between 2016 and 2018. The branching fraction ratios are measured to beB(Ω0c→Ω−K+)B(Ω0c→Ω−π+)=[6.08±0.51(stat)±0.40(syst)]%,B(Ω0c→Ξ−π+)B(Ω0c→Ω−π+)=[15.81±0.87(stat)±0.44(syst)±0.16(ext)]%.In addition, using the Ω0c→Ω−π+ decay channel, the Ω0c baryon mass is measured to be M(Ω0c)=2695.28±0.07(stat)±0.27(syst)±0.30(ext)  MeV, improving the precision of the previous world average by a factor of 4.<br/