Rho-meson properties in medium

TL;DR

This study investigates how the properties of the rho meson change in nuclear matter using a light-front constituent quark model combined with in-medium inputs from the quark-meson coupling model, revealing density-dependent modifications.

Contribution

It applies a light-front constituent quark model to in-medium rho meson properties, providing new predictions on how electromagnetic form factors and moments vary with nuclear density.

Findings

Electromagnetic decay constant increases with density

Charge radius and quadrupole moment are enhanced at higher densities

Zero crossing point of the charge form factor decreases as density increases

Abstract

Properties of $\rho$-meson in symmetric nuclear matter are investigated in a light-front constituent quark model (LFCQM), using the in-medium inputs calculated by the quark-meson coupling (QMC) model. The LFCQM used in this study was already applied for the studies of the electromagnetic properties of $\rho$-meson in vacuum, namely, the charge~$G_0$, magnetic~$G_1$, and quadrupole~$G_2$ form factors, electromagnetic charge radius, and electromagnetic decay constant. We predict that the electromagnetic decay constant, charge radius, and quadrupole moment are enhanced as increasing the nuclear matter density, while the magnetic moment is slightly quenched. Furthermore, we predict that the value $Q^2_{\rm zero}$, which crosses zero of the charge form factor, $G_0(Q^2_{\rm zero})=0$ ($Q^2 = -q^2 > 0$ with $q$ being the four-momentum transfer), decreases as increasing the nuclear matter density.