Screened potential and quarkonia properties at high temperatures

TL;DR

This paper models quarkonia properties at high temperatures using a quark model with string breaking potentials, revealing how different potential types affect quarkonia radii near the deconfining transition, with implications for quark-gluon plasma phenomenology.

Contribution

It introduces a temperature-dependent screening model with smooth and sudden string breaking potentials to study quarkonia spectra near deconfinement.

Findings

Quarkonia radii are nearly temperature-independent up to the critical point with sudden string breaking.

Different potential models lead to qualitatively different quarkonia behaviors near deconfinement.

The results impact understanding of quarkonia dissociation in quark-gluon plasma.

Abstract

We perform a quark model calculation of the quarkonia $b\overline{b}$ and $c\overline{c}$ spectra using smooth and sudden string breaking potentials. The screening parameter is scale dependent and can be related to an effective running gluon mass that has a finite infrared fixed point. A temperature dependence for the screening mass is motivated by lattice QCD simulations at finite temperature. Qualitatively different results are obtained for quarkonia properties close to a critical value of the deconfining temperature when a smooth or a sudden string breaking potential is used. In particular, with a sudden string breaking potential quarkonia radii remain almost independent of the temperature up to the critical point, only well above the critical point the radii increase significantly. Such a behavior will impact the phenomenology of quarkonia interactions in medium, in particular for scattering dissociation processes.