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Abstract

We perform three-dimensional hydrodynamic simulations of aspherical
core-collapse supernovae focusing on the matter mixing in SN 1987A. The impacts
of four progenitor (pre-supernova) models and parameterized aspherical
explosions are investigated. The four pre-supernova models include a blue
supergiant (BSG) model based on a slow merger scenario developed recently for
the progenitor of SN 1987A (Urushibata et al. 2018). The others are a BSG model
based on a single star evolution and two red supergiant (RSG) models. Among the
investigated explosion (simulation) models, a model with the binary merger
progenitor model and with an asymmetric bipolar-like explosion, which invokes a
jetlike explosion, best reproduces constraints on the mass of high velocity
$^{56}$Ni, as inferred from the observed [Fe II] line profiles. The advantage
of the binary merger progenitor model for the matter mixing is the flat and
less extended $\rho \,r^3$ profile of the C+O core and the helium layer, which
may be characterized by the small helium core mass. From the best explosion
model, the direction of the bipolar explosion axis (the strongest explosion
direction), the neutron star (NS) kick velocity, and its direction are
predicted. Other related implications and future prospects are also given.