Three-Dimensional Simulations of Core-Collapse Supernovae: From Shock Revival to Shock Breakout

摘要

We present 3D simulations of core-collapse supernovae from blast-waveinitiation by the neutrino-driven mechanism to shock breakout from the stellarsurface, considering two 15 Msun red supergiants (RSG) and two blue supergiants(BSG) of 15 Msun and 20 Msun. We demonstrate that the metal-rich ejecta inhomologous expansion still carry fingerprints of asymmetries at the beginningof the explosion, but the final metal distribution is massively affected by thedetailed progenitor structure. The most extended and fastest metal fingers andclumps are correlated with the biggest and fastest-rising plumes ofneutrino-heated matter, because these plumes most effectively seed the growthof Rayleigh-Taylor (RT) instabilities at the C+O/He and He/H composition-shellinterfaces after the passage of the SN shock. The extent of radial mixing,global asymmetry of the metal-rich ejecta, RT-induced fragmentation of initialplumes to smaller-scale fingers, and maximal Ni and minimal H velocities do notonly depend on the initial asphericity and explosion energy (which determinethe shock and initial Ni velocities) but also on the density profiles andwidths of C+O core and He shell and on the density gradient at the He/Htransition, which lead to unsteady shock propagation and the formation ofreverse shocks. Both RSG explosions retain a great global metal asymmetry withpronounced clumpiness and substructure, deep penetration of Ni fingers into theH-envelope (with maximum velocities of 4000-5000 km/s for an explosion energyaround 1.5 bethe) and efficient inward H-mixing. While the 15 Msun BSG sharesthese properties (maximum Ni speeds up to ~3500 km/s), the 20 Msun BSG developsa much more roundish geometry without pronounced metal fingers (maximum Nivelocities only ~2200 km/s) because of reverse-shock deceleration andinsufficient time for strong RT growth and fragmentation at the He/H interface.