Chiral transition and mesonic excitations for quarks with thermal masses

We study the effect of a thermal quark mass, m_T, on the chiral phase transition and mesonic excitations in the light quark sector at finite temperature in a simple chirally-symmetric model. We show that while nonzero m_T lowers the chiral condensate, the chiral transition remains of second order. It is argued that the mesonic excitations have large decay rate at energies below 2m_T, owing to the Landau damping of the quarks and the van Hove singularities of the collective modes.