Observation of Cabibbo-Suppressed Two-Body Hadronic Decays and Precision Mass Measurement of the $\Omega_{c}^{0}$ Baryon

TL;DR

This paper reports the first observation of specific Cabibbo-suppressed decays of the ^0 baryon and provides a highly precise measurement of its mass, using LHCb data at 13 TeV.

Contribution

It presents the first observation of ^0 decays to ^-K^+ and ^-^+ and offers a significantly improved mass measurement of the ^0 baryon.

Findings

Branching ratio ^0^-K^+ to ^0^-^+ is 6.08%

Branching ratio ^0^-^+ to ^-^+ is 15.81%

Mass of ^0 baryon measured as 2695.28 MeV

Abstract

The first observation of the singly Cabibbo-suppressed $\Omega_{c}^{0}\to\Omega^{-}K^{+}$ and $\Omega_{c}^{0}\to\Xi^{-}\pi^{+}$ decays is reported, using proton-proton collision data at a center-of-mass energy of $13\,{\rm TeV}$, corresponding to an integrated luminosity of $5.4\,{\rm fb}^{-1}$, collected with the LHCb detector between 2016 and 2018. The branching fraction ratios are measured to be $\frac{\mathcal{B}(\Omega_{c}^{0}\to\Omega^{-}K^{+})}{\mathcal{B}(\Omega_{c}^{0}\to\Omega^{-}\pi^{+})}=[6.08\pm0.51({\rm stat})\pm0.40({\rm syst})]\%$, $\frac{\mathcal{B}(\Omega_{c}^{0}\to\Xi^{-}\pi^{+})}{\mathcal{B}(\Omega_{c}^{0}\to\Omega^{-}\pi^{+})}=[15.81\pm0.87({\rm stat})\pm0.44({\rm syst})\pm0.16({\rm ext})]\%$. In addition, using the $\Omega_{c}^{0}\to\Omega^{-}\pi^{+}$ decay channel, the $\Omega_{c}^{0}$ baryon mass is measured to be $M(\Omega_{c}^{0})=2695.28\pm0.07({\rm stat})\pm0.27({\rm syst})\pm0.30({\rm ext})\,{\rm MeV}$, improving the precision of the previous world average by a factor of 4.