Study of $P$-wave excitations of observed charmed strange baryons

TL;DR

This study systematically analyzes the strong decay properties of observed excited charmed strange baryons using a $^3P_0$ model to determine their internal structure and spin-parities, providing specific $P$-wave excitation assignments.

Contribution

It offers new assignments of $P$-wave excited $ ext{Xi}_c$ baryons based on decay analysis, clarifying their possible internal configurations and quantum numbers.

Findings

$ ext{Xi}_c(3055)$, $ ext{Xi}_c(3080)$, $ ext{Xi}_c(3123)$ are unlikely $P$-wave excitations.

$ ext{Xi}_c(2790)$ and $ ext{Xi}_c(2815)$ are likely $ ext{P}$-wave excited $ ext{Xi}_{c1}$ states.

Predicted branching fraction ratios can help future experimental identification.

Abstract

Many excited charmed strange baryons such as $\Xi_c(2790)$, $\Xi_c(2815)$, $\Xi_c(2930)$, $\Xi_c(2980)$, $\Xi_c(3055)$, $\Xi_c(3080)$ and $\Xi_c(3123)$ have been observed. In order to understand their internal structure and to determine their spin-parities, the strong decay properties of these baryons as possible $P$-wave excited $\Xi_c$ candidates have been systematically studied in a $^3P_0$ model. The configurations and $J^P$ assignments of $\Xi_c(2790)$, $\Xi_c(2815)$, $\Xi_c(2930)$, $\Xi_c(2980)$, $\Xi_c(3055)$, $\Xi_c(3080)$ and $\Xi_c(3123)$ have been explored based on recent experimental data. In our analyses, $\Xi_c(3055)$, $\Xi_c(3080)$ and $\Xi_c(3123)$ seem impossible to be the $P$-wave excited $\Xi_c$. $\Xi_c(2790)$, $\Xi_c(2815)$, $\Xi_c(2930)$ and $\Xi_c(2980)$ may be the $P$-wave excited $\Xi_c$. In particular, $\Xi_c(2790)$ and $\Xi_c(2815)$ are very possibly the $P$-wave excited $\Xi_{c1}(1/2^-)$ and $\Xi_{c1}(3/2^-)$, respectively. $\Xi_c(2980)$ may be the $P$-wave excited $\Xi_{c1}^{'}(\frac{1}{2}^-)$. $\Xi_c(2930)$ may be the $P$-wave $\Xi_{c0}^{'}(\frac{1}{2}^-)$, $\tilde{\Xi}_{c0}(\frac{1}{2}^-)$, $\Xi_{c2}^{'}(\frac{3}{2}^-)$, $\Xi_{c2}^{'}(\frac{5}{2}^-)$, $\tilde{\Xi}_{c2}(\frac{3}{2}^-)$ or $\tilde{\Xi}_{c2}(\frac{5}{2}^-)$. Furthermore, some branching fraction ratios related to the internal structure and quark configuration of $P$-wave $\Xi_c$ have also been computed. Measurements of these ratios in the future will be helpful to understand these excited $\Xi_c$.