Establishing low-lying doubly charmed baryons

TL;DR

This paper uses QCD sum rules to analyze doubly charmed baryons, identifying the $ ext{Xi}_{cc}^{++}$ state and predicting masses for other related states, aiding understanding of strong interaction structures.

Contribution

It provides a systematic QCD sum rule analysis of both S-wave and P-wave doubly charmed baryons, including mass predictions and identification of recently observed states.

Findings

$ ext{Xi}_{cc}^{++}$ is identified as an $S$-wave $J^P=1/2^+$ state.

Predicted mass of $ ext{Omega}_{cc}$ around 3.7 GeV.

Predicted P-wave doubly charmed baryon masses around 4.1 GeV.

Abstract

We systematically study the $S$-wave doubly charmed baryons using the method of QCD sum rules. Our results suggest that the $\Xi_{cc}^{++}$ recently observed by LHCb can be well identified as the $S$-wave $\Xi_{cc}$ state of $J^P = 1/2^+$. We study its relevant $\Omega_{cc}$ state, whose mass is predicted to be around 3.7 GeV. We also systematically study the $P$-wave doubly charmed baryons, whose masses are predicted to be around 4.1 GeV. Especially, there can be several excited doubly charmed baryons in this energy region, and we suggest to search for them in order to study the fine structure of the strong interaction.