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Gravitational Collapse of a Massless Scalar Field in a Periodic Box
Chul-Moon Yoo, Taishi Ikeda, Hirotada Okawa
Gravitational collapse of a massless scalar field with the periodic boundary condition in a cubic box is reported. This system can be regarded as a lattice universe model. We const…
On the Neutrino Distributions in Phase Space for the Rotating Core-collapse Supernova Simulated with a Boltzmann-neutrino-radiation-hydrodynamics Code
Akira Harada, Hiroki Nagakura, Wakana Iwakami +5
With the Boltzmann-radiation-hydrodynamics code, which we have developed to solve numerically the Boltzmann equations for neutrino transfer, the Newtonian hydrodynamics equations,…
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…
Maximal Efficiency of Collisional Penrose Process with Spinning Particles
Kei-ichi Maeda, Kazumasa Okabayashi, Hirotada Okawa
We analyze collisional Penrose process of spinning test particles in an extreme Kerr black hole. We consider that two particles plunge into the black hole from infinity and collide…