Properties of a hyperon-quark mixed phase in compact stars

Maruyama, Toshiki  ; Chiba, Satoshi; Schulze, H.-J.*; Tatsumi, Toshitaka*

We investigate the property of the hadron-quark mixed phase using the Brueckner-Hartree-Fock model for hadron (hyperon) phase and the MIT bag model for quark phase. To satisfy the Gibbs conditions, charge density as well as baryon number density becomes non-uniform in the mixed phase. Taking into account the density distribution and the Coulomb interaction in a self-consistent way, we clarify the roles of the surface tension and the charge screening effect. We will show that the screened Coulomb interaction makes the EOS similar to the one given by the Maxwell construction. We demonstrate that hyperons are suppressed in the mixed phase, because hadron phase is positively charged. This is a novel mechanism of hyperon suppression in compact stars. Finally we will discuss some consequences of our EOS on the structure and the maximum mass of NS.