Lowest lying even-parity $\bar B_s$ mesons: heavy quark spin-flavor symmetry, chiral dynamics, and constituent quark model bare masses

TL;DR

This paper investigates the lowest lying even-parity $ar B_s$ mesons using heavy quark symmetry, chiral dynamics, and constituent quark models, focusing on their interactions with meson channels and lattice data to predict properties of unobserved states.

Contribution

It introduces a novel approach combining quark models, heavy quark symmetry, and lattice constraints to analyze bottom-strange mesons and their coupling to meson channels.

Findings

Predicted properties of bottom-strange scalar and axial mesons.

Demonstrated the importance of meson loop effects near thresholds.

Provided a framework consistent with lattice QCD results.

Abstract

The discovery of the $D^\ast_{s0}(2317)$ and $D_{s1}(2460)$ resonances in the charmed-strange meson spectra revealed that formerly successful constituent quark models lose predictability in the vicinity of two-meson thresholds. The emergence of non-negligible effects due to meson loops requires an explicit evaluation of the interplay between $Q\bar q$ and $(Q\bar q)(q\bar q)$ Fock components. In contrast to the $c\bar s$ sector, there is no experimental evidence of $J^P=0^+,1^+$ bottom-strange states yet. Motivated by recent lattice studies, in this work the heavy-quark partners of the $D_{s0}^\ast(2317)$ and $D_{s1}(2460)$ states are analyzed within a heavy meson chiral unitary scheme. As a novelty, the coupling between the constituent quark model P-wave $\bar B_s$ scalar and axial mesons and the $\bar B^{(\ast)}K$ channels is incorporated employing an effective interaction, consistent with heavy quark spin symmetry, constrained by the lattice energy levels.