Item

Abstract

We perform a new general-relativistic viscous-radiation hydrodynamics
simulation for supernova-like explosion associated with stellar core collapse
of rotating massive stars to a system of a black hole and a massive torus
paying particular attention to large-mass progenitor stars with the zero-age
main-sequence mass of $M_\mathrm{ZAMS}=$20, 35, and 45$M_\odot$ of
Ref.~\cite{Aguilera-Dena2020oct}. Assuming that a black hole is formed in a
short timescale after the onset of the stellar collapse, the new simulations
are started from initial data of a spinning black hole and infalling matter
that self-consistently satisfy the constraint equations of general relativity.
It is found that with a reasonable size of the viscous parameter, the
supernova-like explosion is driven by the viscous heating effect in the torus
around the black hole irrespective of the progenitor mass. The typical
explosion energy and ejecta mass for the large-mass cases ($M_\mathrm{ZAMS}=35$
and $45M_\odot$) are $\sim 10^{52}$ erg and $\sim 5M_\odot$, respectively, with
$^{56}$Ni mass larger than $0.15M_\odot$. These are consistent with the
observational data of stripped-envelope and high-energy supernovae such as
broad-lined type Ic supernovae. This indicates that rotating stellar collapses
of massive stars to a black hole surrounded by a massive torus can be a central
engine for high-energy supernovae. By artificially varying the angular velocity
of the initial data, we explore the dependence of the explosion energy and
ejecta mass on the initial angular momentum and find that the large explosion
energy $\sim 10^{52}$ erg and large $^{56}$Ni mass $\geq 0.15M_\odot$ are
possible only when a large-mass compact torus with mass $\gtrsim 1M_\odot$ is
formed.