DYNAMICAL AND THERMAL EVOLUTION OF THE QUARK-NOVA EJECTA

We explore the dynamical and thermal evolution of the ejected neutron star crust in a quark-nova explosion. Typical explosion energies and ejected crust masses result in relativistic ejection with Lorentz factors of a few to a few hundreds. The ejecta undergoes a rapid cooling and stretching resulting in break up into many small pieces (clumps) when the ejecta is only ∼100 km from the explosion site. The number and size of the clumps depend on whether the breakup occurs in the liquid or solid phase. For these two cases, the clump number is ∼103 (liquid phase) or ∼107 (solid phase) and, at break up, are spherical (size ∼104 cm; liquid phase) or needle shaped (∼104 × 102 cm; solid phase).