32 citations · 110 across the 9 of their papers we have counts for
9 papers
A Lagrangian construction of rotating stars
Misa Ogata, Hirotada Okawa, Kotaro Fujisawa +3
We present a new formulation for numerically obtaining axisymmetric equilibrium structures of rotating stars in two spatial dimensions. With a view to apply it to the secular evolu…
A novel formulation for the evolution of relativistic rotating stars
Hirotada Okawa, Kotaro Fujisawa, Nobutoshi Yasutake +3
We present a new formulation to construct numerically equilibrium configurations of rotating stars in general relativity. Having in mind the application to their quasi static evolu…
Singularity-Avoiding Multi-Dimensional Root-Finder
Hirotada Okawa, Kotaro Fujisawa, Yu Yamamoto +3
We proposed in this paper a new method, which we named the W4 method, to solve nonlinear equation systems. It may be regarded as an extension of the Newton-Raphson~(NR) method to b…
On the importance of progenitor asymmetry to shock revival in core-collapse supernovae
Hiroki Nagakura, Kazuya Takahashi, Yu Yamamoto
The progenitor stars of core-collapse supernovae (CCSNe) are asymmetrically fluctuating due to turbulent convections in the late stages of their lives. The progenitor asymmetry at…
The W4 method: a new multi-dimensional root-finding scheme for nonlinear systems of equations
Hirotada Okawa, Kotaro Fujisawa, Yu Yamamoto +4
We propose a new class of method for solving nonlinear systems of equations, which, among other things,has four nice features: (i) it is inspired by the mathematical property of da…
Effects of rotation and magnetic field on the revival of a stalled shock in supernova explosions
Kotaro Fujisawa, Hirotada Okawa, Yu Yamamoto +1
We investigate axisymmetric steady solutions of (magneto)hydrodynamics equations that describe approximately accretion flows through a standing shock wave and discuss the effects o…
Links between the shock instability in core-collapse supernovae and asymmetric accretions of envelopes
Kazuya Takahashi, Wakana Iwakami, Yu Yamamoto +1
The explosion mechanism of core-collapse supernovae has not been fully understood yet but multi-dimensional fluid instabilities such as standing accretion shock instability (SASI)…
Post-shock-revival evolutions in the neutrino-heating mechanism of core-collapse supernovae
Yu Yamamoto, Shin-ichiro Fujimoto, Hiroki Nagakura +1
We perform some experimental simulations in spherical symmetry and axisymmetry to understand the post-shock-revival evolution of core-collapse supernovae. Assuming that the stalled…
Semi-dynamical approach to the shock revival in core-collapse supernovae
Hiroki Nagakura, Yu Yamamoto, Shoichi Yamada
We develop a new semi-dynamical method to study shock revival by neutrino heating in core- collapse supernovae. Our new approach is an extension of the previous studies that employ…