Color superconductor with a color-sextet condensate

We analyze color superconductivity of one massive flavor quark matter at moderate baryon density with a spin-zero color-sextet condensate. The most general form of the order parameter implies complete breakdown of the SU(3)× U(1) symmetry. However, both the conventional fourth-order polynomial effective bosonic description and the fermionic NJL-type model in the mean-field approximation favor an enhanced O(3) symmetry of the ground state. We suggest two mechanisms how the complete symmetry breakdown could be achieved.