Characterizing the Directional Dependence of Gravitational Wave Emission from Core-collapse Supernovae*

Core-collapse supernovae (CCSNe) enrich the universe with successively refined elements and new compact objects, with each generation of massive stars.  One signal of interest from these stellar explosions are gravitational waves (GWs).  These spacetime ripples encode interesting internal physics such as how matter behaves at nuclear densities, hydrodynamic activity, and neutrino production, among others.  With a wealth of potential information from GWs, astronomers remain poised to interpret gravitational waveforms from these yet undetected sources.  Beyond learning new kinds of physics, quantifying the directionality of GW emission is a crucial consideration with respect to observability.   

 

In this talk, I use results from 3D CCSN simulations to introduce a new visualization method that characterizes the distribution of GW emission over all viewing angles.  I will show CCSNe do not have a single ‘optimal’ viewing angle, along which the strongest GWs can be detected; rather, this ‘preferred direction’ can drift throughout the CCSN evolution.  Moreover, rotating CCSNe have a preferred direction of GW generation that may precess around the axis of rotation for both polarization modes.