  If the phase transition of $QCD$ at nonzero temperature is dominated by the
(approximate) restoration of chiral symmetry, then the transition might be
characterized using a gauged linear sigma model. Assuming that vector meson
dominance holds, such sigma models predict that at the temperature of chiral
restoration, the pole mass of the thermal $\rho$ meson is greater than that at
zero temperature; in the chiral limit and in weak coupling this mass is $\sim
962 \, MeV$. The width of the thermal $\rho-a_1$ peak is estimated to be about
$200 - 250 \, MeV$.
