Strong Decays of the Light Exotic $0^{+-}$ and $2^{+-}$ Hybrid Mesons

TL;DR

This paper models the decay of exotic hybrid mesons with quantum numbers $0^{+-}$ and $2^{+-}$ using a Coulomb gauge QCD Hamiltonian, revealing that these states are narrower than previously thought due to specific decay suppression.

Contribution

It introduces a new decay calculation for hybrid mesons based on a Coulomb gauge QCD model with a quasigluon, highlighting unique decay suppression effects.

Findings

$0^{+-}$ states are narrow, contrary to previous results.

Decay suppression of $0^{+-} ightarrow 2^1S_0+1^1S_0$ is significant.

$2^{+-}$ states are also narrow.

Abstract

A model of hybrid meson structure based on the QCD Hamiltonian in Coulomb gauge and the use of a single constituent quasigluon is applied compute hadronic decays of mesons with exotic quantum numbers, $0^{+-}$ and $2^{+-}$. These correspond to hybrid mesons in which the gluon couples to a $q\bar{q}$ pair in an $P$-wave and can therefore be identified as orbital excitations of the exotic $1^{-+}$ state. Interestingly, we find $0^{+-}$ states to be narrow, contrary to what was found by previous calculations. This is primarily due to the suppression of the decay mode $0^{+-}\rightarrow 2^1S_0+1^1S_0$, which is unique to our model. The $2^{+-}$ states are found to be narrow, as expected.