Reanalysis of $\Omega_c \rightarrow \Xi_c^+ K^-$ decay in QCD

TL;DR

This paper estimates the strong coupling constants and decay widths of $ ext{Omega}_c$ baryons decaying into $ ext{Xi}_c^+ K^-$ using light cone QCD sum rules, and compares predictions with experimental data, ruling out two quantum number scenarios.

Contribution

The study provides the first QCD sum rule analysis of $ ext{Omega}_c$ decay widths considering two different quantum number scenarios, and finds both are inconsistent with experimental data.

Findings

Predicted decay widths differ significantly from experimental values.

Both considered quantum number scenarios are incompatible with observed decay data.

The results suggest the need for alternative quantum number assignments for $ ext{Omega}_c$ baryons.

Abstract

The strong coupling constants of newly observed $\Omega_c^0$ baryons with spin $J = \frac{1}{2}$ and $J = \frac{3}{2}$ decaying into $\Xi_c^{+} K^{-}$ are estimated within light cone QCD sum rules. The calculations are performed within two different scenarios on quantum numbers of $\Omega_c$ baryons: a) all newly observed $\Omega_c$ baryons are negative parity baryons, i.e., the $\Omega_c(3000)$, $\Omega_c(3050)$, $\Omega_c(3066)$, and $\Omega_c(3090)$ have quantum numbers $J^P = \frac{1}{2}^-$ and $J^P = \frac{3}{2}^-$ states respectively; b) the states $\Omega_c(3000)$ and $\Omega_c(3050)$ have quantum numbers $J^P = \frac{1}{2}^-$ and $J^P = \frac{1}{2}^+$, while the states $\Omega_c(3066)$ and $\Omega_c(3090)$ have the quantum numbers $J^P = \frac{3}{2}^-$ and $J^P = \frac{3}{2}^+$, respectively. By using the obtained results on the coupling constants, we calculate the decay widths of the corresponding decays. The results on decay widths are compared with the experimental data of LHC Collaboration. We found out that the predictions on decay widths within these scenarios are considerably different from the experimental data, i.e., both considered scenarios are ruled out.