# Masses of ground-state mesons and baryons, including those with heavy quarks

## TL;DR

This paper calculates the masses of ground-state mesons and baryons, including heavy-quark states, using a symmetry-preserving contact interaction, achieving high accuracy and predicting new heavy baryons.

## Contribution

It introduces a largely algebraic, diquark-based approach to compute baryon spectra, emphasizing the dynamical role of diquark correlations.

## Key findings

- Reproduces 22 known experimental baryon masses with ~3% accuracy.
- Predicts many heavy-quark baryons not yet observed.
- Highlights the importance of diquark correlations in baryon structure.

## Abstract

Using a confining, symmetry-preserving regularisation of a vector$\times$vector contact interaction, we compute the spectra of ground-state pseudoscalar and vector $(f\bar g)$ mesons, scalar and axial-vector $(fg)$ diquarks, and $J^P=1/2^+, 3/2^+$ $(fgh)$ baryons, where $f,g,h \in \{u,d,s,c,b\}$. The diquark correlations are essentially dynamical and play a key role in formulating and solving the three-valence-quark baryon problems. The baryon spectrum obtained from this largely-algebraic approach reproduces the 22 known experimental masses with an accuracy of $2.9(2.4)$%. It also possesses the richness of states typical of constituent-quark models, predicting many heavy-quark baryons not yet observed. This study indicates that diquark correlations are an important component of all baryons; and owing to the dynamical character of the diquarks, it is typically the lightest allowed diquark correlation which defines the most important component of a baryon's Faddeev amplitude.