Light Flavour and Heavy Quark Spin Symmetry in Heavy Meson Molecules

TL;DR

This paper develops an effective field theory using light SU(3) flavor and heavy quark spin symmetries to analyze charmed meson-antimeson molecules, constraining their interactions and predicting their spectrum.

Contribution

It introduces a simplified contact interaction model incorporating symmetries to study heavy meson molecules and constrains possible molecular states based on decay data.

Findings

Ruled out isovector partner of X(3872)

Determined spectrum of molecular states with various isospins

Constrained meson-antimeson interactions using decay data

Abstract

We propose an effective field theory incorporating light SU(3)-flavour and heavy quark spin symmetry to describe charmed meson-antimeson bound states. At lowest order the effective field theory entails a remarkable simplification: it only involves contact range interactions among the heavy meson and antimeson fields. We show that the isospin violating decays of the X(3872) can be used to constraint the interaction between the $D$ and a $\bar{D}^*$ mesons in the isovector channel. As a consequence, we can rule out the existence of a isovector partner of the X(3872). If we additionally assume that the X(3915) and Y(4140) are $D^*\bar{D}^*$ and $D_s^*\bar{D}_s^*$ molecular states, we can determine the full spectrum of molecular states with isospin I=0, 1/2 and 1.