  We investigate the consequences of enforcing local color neutrality on the
color superconducting phases of quark matter by utilizing the
Nambu-Jona-Lasinio model supplemented by diquark and the t'Hooft six-fermion
interactions. In neutrino free matter at zero temperature, color neutrality
guarantees that the number densities of u, d, and s quarks in the
Color-Flavor-Locked (CFL) phase will be equal even with physical current quark
masses. Electric charge neutrality follows as a consequence and without the
presence of electrons. In contrast, electric charge neutrality in the less
symmetric 2-flavor superconducting (2SC) phase with ud pairing requires more
electrons than the normal quark phase. The free energy density cost of
enforcing color and electric charge neutrality in the CFL phase is lower than
that in the 2SC phase, which favors the formation of the CFL phase. With
increasing temperature and neutrino content, an unlocking transition occurs
from the CFL phase to the 2SC phase with the order of the transition depending
on the temperature, the quark and lepton number chemical potentials. The
astrophysical implications of this rich structure in the phase diagram,
including estimates of the effects from Goldstone bosons in the CFL phase, are
discussed.
