Higher charmonia and bottomonia. Nature of the X(3872)

TL;DR

This paper uses an unquenched quark model to analyze the spectra and decay properties of higher charmonia and bottomonia, focusing on the nature of the X(3872) as a mixed state with a cc core and meson-meson components.

Contribution

It provides a detailed unquenched quark model analysis of heavy quarkonium spectra and the structure of X(3872), incorporating continuum effects and decay calculations.

Findings

Spectra calculated with self-energy corrections match experimental data.

X(3872) described as a superposition of cc core and meson-meson continuum.

Decay properties support the mixed-state interpretation of X(3872).

Abstract

In this contribution, we will discuss our unquenched quark model re- sults for the spectra of cc and bb states. The spectra are calculated in the unquenched quark model formalism, where the physical mass of a meson is the sum of a bare mass contribution plus a self-energy correc- tion, due to the coupling to the meson-meson continuum. We will also discuss the quark structure of the X(3872). Its open-flavor and radiative decays are calculated in the quark model formalism. In our interpreta- tion, the wave function of the X(3872) is the sum of two contributions, a cc core plus higher Fock components, due to meson-meson continuum components. Our results for the spectra, open-flavor and radiative decays are compared to the existing experimental data.