Misc,
Impacts of Rotation on Three-dimensional Hydrodynamics of Core-collapse Supernovae
(Mar 28, 2014)
Abstract
We perform a series of simplified numerical experiments to explore how
rotation impacts on the three-dimensional (3D) hydrodynamics of core-collapse
supernovae. For the sake of our systematic study, we employ a light-bulb scheme
to trigger explosions and a three-flavor neutrino leakage scheme to treat
deleptonization effects and neutrino losses from proto-neutron star interior.
Using a 15 solar mass progenitor, we compute thirty models in 3D with a wide
variety of initial angular momentum and light-bulb neutrino luminosity. We find
that the rotation can help onset of neutrino-driven explosions for the models
in which the initial angular momentum is matched to that obtained in recent
stellar evolutionary calculations (0.3-3 rad/s at the center). For models with
larger initial angular momentum, a shock surface deforms to be more oblate due
to larger centrifugal force. This makes not only a gain region more
concentrated around the equatorial plane, but also the mass in the gain region
bigger. As a result, buoyant bubbles tend to be coherently formed and rise in
the equatorial region, which pushes the revived shock ever larger radii until a
global explosion is triggered. We find that these are the main reasons that the
preferred direction of explosion in 3D rotating models is often perpendicular
to the spin axis, which is in sharp contrast to the polar explosions around the
axis that was obtained in previous 2D simulations.
