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.

Figures and captions

Invariant-mass distributions for (left) $\Omega ^0_ c \rightarrow \Omega ^- K ^+ $ , (middle) $\Omega ^0_ c \rightarrow \Xi ^- \pi ^+ $ , and (right) $\Omega ^0_ c \rightarrow \Omega ^- \pi ^+ $ decays.	Fig1a.pdf [63 KiB] HiDef png [276 KiB] Thumbnail [239 KiB] *.C file
	Fig1b.pdf [60 KiB] HiDef png [241 KiB] Thumbnail [206 KiB] *.C file
	Fig1c.pdf [59 KiB] HiDef png [241 KiB] Thumbnail [177 KiB] *.C file
Animated gif made out of all figures.	PAPER-2023-011.gif Thumbnail

Tables and captions

Systematic uncertainties for the $\Omega ^0_ c $ mass measurement.	Table_1.pdf [39 KiB] HiDef png [52 KiB] Thumbnail [24 KiB] tex code
Systematic uncertainties (in percentages) for the BF ratio measurement.	Table_2.pdf [65 KiB] HiDef png [81 KiB] Thumbnail [36 KiB] tex code

Created on 27 April 2024.