Dilepton Production from Meson Condensed Matter

Dilepton production from meson condensed hadronic matter is studied based on the vector meson dominance (VMD) hypothesis, where the hadronic electro-magnetic (EM) current is a linear combination of the neutral vector meson fields. In the presence of the pseudo-scalar meson condensate, the vector and the axial-vector mesons are mixed to form quasi-particles, and the hadronic EM current is proved to be a linear combination of the quasi-particle fields of the "vector" and the "axial-vector". As a result, we find that an axial-vector-like contribution appears in the dilepton spectrum from the meson condensed matter. for two cases, the pion and the kaon condensations, we explicitly calculate the electron-pair spectrum and discuss its characteristic modifications.