  We compute the masses of the pseudoscalar mesons $\pi^+$ , $K^0$ and $D^+$ at
finite temperature and baryon chemical potential. The computations are based on
a symmetry- preserving Dyson-Schwinger equation treatment of a vector-vector
four quark contact interaction. The results found for the temperature
dependence of the meson masses are in qualitative agreement with lattice QCD
data and QCD sum rules calculations. The chemical potential dependence of the
masses provide a novel prediction of the present computation.

Nuclear Theory