Identification of the newly observed $\Sigma_b(6097)^\pm$ baryons from their strong decays

TL;DR

This paper analyzes the newly observed $oldsymbol{ ext{Σ}_b(6097)^ ext{±}}$ baryons, using decay models to propose their quantum states and predict decay widths consistent with experimental data, aiding in understanding bottom baryon spectroscopy.

Contribution

The study systematically computes decay widths of $ ext{Σ}_b$ baryons using a $^{3}P_{0}$ model and suggests possible quantum state assignments for the $ ext{Σ}_b(6097)^ ext{±}$ baryons, providing predictions for future experimental tests.

Findings

The $ ext{Σ}_b(6097)^ ext{±}$ are likely $ ext{Σ}_{b2}^1({3/2}^-)$ or $ ext{Σ}_{b2}^1({5/2}^-)$ states.

Predicted decay widths match experimental measurements from LHCb.

Ratios of decay widths could distinguish between the two quantum state assignments.

Abstract

Two bottom $\Sigma_b(6097)^\pm$ baryons were observed in the final states $\Lambda_b^0\pi^-$ and $\Lambda_b^0\pi^+$ in $pp$ collision by LHCb collaboration, whose masses and widths were measured. In a $^{3}P_{0}$ model, the strong decay widths of two ground $S$-wave and seven excited $P$-wave $\Sigma_b$ baryons have been systematically computed. Numerical results indicate that the newly observed $\Sigma_b(6097)^\pm$ are very possibly $\Sigma_{b2}^1({3\over 2}^-)$ with $J^P={3\over 2}^-$ or $\Sigma_{b2}^1({5\over 2}^-)$ with $J^P={5\over 2}^-$. The predicted decay widths of $\Sigma_b(6097)^\pm$ are consistent with experimental measurement from LHCb. In particular, it may be possible to distinguish these two assignments through ratios $\Gamma({\Sigma_b(6097)^\pm\to \Sigma_b^\pm\pi^0})/\Gamma({\Sigma_b(6097)^\pm\to \Sigma_b^{*\pm}\pi^0})$, which can be measured by experiments in the future. In the meantime, our results support the assignments that $\Sigma_b^\pm$ and $\Sigma_b^{*\pm}$ are the ground $S$-wave $\Sigma_b$ baryons with $J^P={1\over 2}^+$ and $J^P={3\over 2}^+$, respectively.