Neutron stars with a stable, light supersymmetric baryon

If a light gluino exists, the lightest gluino-containing baryon, S-0, is a possible candidate for self-interacting dark matter. In this scenario, the simplest explanation for the observed ratio Omega (DM)/Omega (b) approximat e to 6-10 is that m(s0) similar to 900 MeV c(-2); at present, this is not e xcluded by particle physics. Such an S-0 could be present in neutron stars, with the hyperon formation serving as an intermediate stage. We calculate equilibrium compositions and the equation of state for high-density matter with S-0, and we find that for a wide range of parameters, the properties o f neutron stars with S-0 are consistent with observations. In particular, t he maximum mass of a nonrotating star is 1.7- 1.8 M-., and the presence of S-0 is helpful in reconciling observed cooling rates with hyperon formation .