Effect of vector--axial-vector mixing to dilepton spectrum

Abstract

In this write-up we summarize main results of our recent analyses on the mixing between transverse rho and a1 mesons in hot and/or dense matter. We show that the axial-vector meson contributes significantly to the vector spectral function in hot matter through the mixing. In dense baryonic matter, we include a mixing through a set of omega rho a1 -type interactions. We show that a clear enhancement of the vector spectral function appears below \sqrt{s}=m_ρfor small three-momenta of the rho meson, and thus the vector spectrum exhibits broadening.

Contribution to the proceedings of 2009 Nagoya Global COE Workshop "Strong Coupling Gauge Theories in LHC Era (SCGT09)"