Color superconductivity in asymmetric matter

The influence on color superconductivity of the presence of unequal chemical potentials for different quark flavors is analyzed. It is found in a mean-field approximation that there is a first order transition as this asymmetry grows. This transition proceeds through the formation of bubbles of low density, flavor asymmetric normal phase inside a high density, superconducting phase that has a gap larger than the one found in the symmetric case. For small fixed asymmetries the system is normal at low densities and superconducting only above some critical density. For larger asymmetries the system stays in the mixed state for arbitrarily high densities. (C) 2002 Elsevier Science B.V.. All fights reserved.