Princeton University Astroplasmas Seminar

TALK TIME MOVED TO 1:15 PM! Abstract - In this talk I will present two of my recent projects. The first is the analytic study of a bow shock with infinite mach number. We show that in this case the shock will not converge to a mach cone, but rather to a parabolic solid of revolution. We calculate the hydrodynamic profiles inside the bow shock, and verify our results using a numerical simulation. We use our model to characterise a bow shock around an isolated neutron star. The second project is the analysis of spherical relativistic shock breakout. Previous works studied the case where an outward moving shock accelerates matter in the stellar atmosphere, but the post shock acceleration ends before a fluid element travels a distance comparable to the stellar radius. Unfortunately, this formalism is only valid for low values of the Lorentz factor. In this work, we extend the formalism to higher values of the Lorentz factor, where the acceleration ends at distances much larger than the initial radius. We verify our results with a numerical simulation, and make predictions about the lightcurves and spectra from such breakouts. Finally, we discuss the question whether such events can occur in an astrophysical explosions.