Glueballs and the superfluid phase of Two-Color QCD

TL;DR

This study investigates scalar glueballs in cold, dense two-color QCD using lattice simulations, revealing significant changes in gluonic properties across the superfluid phase transition.

Contribution

First lattice simulation of scalar glueballs in dense two-color QCD, showing how gluonic states are affected by superfluid phase transition.

Findings

Glueball correlator amplitude peaks at chiral transition

Mass in the 0++ channel decreases in superfluid phase

Gluonic medium undergoes nontrivial modifications at nonzero density

Abstract

We present the first results on scalar glueballs in cold, dense matter using lattice simulations of two color QCD. The simulations are carried out on a $6^3 \times 12$ lattice and use a standard hybrid molecular dynamics algorithm for staggered fermions for two values of quark mass. The glueball correlators are evaluated via a multi-step smearing procedure. The amplitude of the glueball correlator peaks in correspondence with the zero temperature chiral transition, $\mu_c = m_\pi/2$, and the propagators change in a significant way in the superfluid phase, while the Polyakov loop is mearly insensitive to the transition. Standard analysis suggest that lowest mass in the $0^{++}$ gluonic channel decreases in the superfluid phase, but these observations need to be confirmed on larger and more elongated lattices These results indicate that a nonzero density induces nontrivial modifications of the gluonic medium.