Bethe-Salpeter kernel and properties of strange-quark mesons

TL;DR

This paper develops a symmetry-consistent Bethe-Salpeter kernel method for calculating properties of strange-quark mesons, providing insights into meson spectra, decay constants, and the emergence of mass in the standard model.

Contribution

It introduces a novel, symmetry-preserving approach to compute meson spectra and decay constants using Bethe-Salpeter kernels compatible with gluon-quark vertices.

Findings

Predicted masses of unobserved meson states

Calculated decay constants for ground and excited states

Highlighted the importance of emergent hadron mass in meson properties

Abstract

Focusing on the continuum meson bound-state problem, a novel method is used to calculate closed-form Bethe-Salpeter kernels that are symmetry consistent with any reasonable gluon-quark vertex, $\Gamma_\nu$, and therewith deliver a Poincar\'e-invariant treatment of the spectrum and decay constants of the ground- and first-excited states of $u$, $d$, $s$ mesons. The predictions include masses of as-yet unseen states and many unmeasured decay constants. The analysis reveals that a realistic, unified description of meson properties (including level orderings and mass splittings) requires a sound expression of emergent hadron mass in bound-state kernels; alternatively, that such properties may reveal much about the emergence of mass in the standard model.