In this dissertation, the structure and evolution of neutron stars containing deconfined quark matter are investigated. The essential microphysical ingredients, the equation of state and the associated neutrino opacity that govern the macrophysical evolution of a neutron star, are calculated and utilized in the first self- consistent dynamical calculation of a proto-neutron star containing quark matter. It is shown that neutrino trapping inhibits the appearance of a mixed phase that leads to proto-neutron star metastability. Sufficiently massive stars containing negatively-charged, strongly interacting, particles (including quarks) may collapse to black holes during the first minute of evolution. In addition, the specific heat of the quark-hadron mixed phase is found to be much larger than that of the kaon condensate-hadron mixed phase. This produces core temperatures significantly lower in stars containing quarks than in those not containing quarks. Neutrino opacities in quark matter are calculated for the neutrino degeneracies and lepton contents encountered in a protoneutron star's evolution. It is shown that the appearance of quarks in baryonic matter drastically reduces the neutrino opacity for a given entropy. Neutrino fluxes are calculated from proto-neutron stars with and without quarks. Because the neutrino flux would vanish if a black hole forms, metastability provides an obvious signal that quarks (or other types of strange matter) have appeared. The metastability timescales for stars with quarks are intermediate between those containing hyperons and kaon condensates. The consequences of enforcing local color neutrality on the color superconducting phases of quark matter are investigated. At zero temperature, the energy cost of enforcing color and electric charge neutrality in the color-flavor-locked (CFL) phase is lower than that in the two-flavor-superconducting (2SC) phase, which favors the formation of the CFL phase. With increasing temperature and neutrino content, however, an unlocking transition occurs from the CFL phase to the 2SC phase. A new phase diagram for quark-hadron matter is presented. The CFL phase is unlikely to appear until after the neutrinos have left the star. The astrophysical implications of the structure of this phase diagram are discussed.
- Pub Date:
- Physics: Nuclear, Physics: Astronomy and Astrophysics