431 citations · 2.2k across the 37 of their papers we have counts for
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Axisymmetric Magnetorotational Instability in Viscous Accretion Disks
Youhei Masada, Takayoshi Sano
Axisymmetric magnetorotational instability (MRI) in viscous accretion disks is investigated by linear analysis and two-dimensional nonlinear simulations. The linear growth of the v…
Dead Zone Formation and Nonsteady Hyperaccretion in Collapsar Disks : A Possible Origin of Short-Term Variability in the Prompt Emission of Gamma-Ray Bursts
Youhei Masada, Norita Kawanaka, Takayoshi Sano +1
The central engine of gamma-ray bursts (GRBs) is believed to be a hot and dense disk with hyperaccretion onto a few solar-mass black hole. We investigate where the magnetorotationa…
The Effect of Neutrino Radiation on Magnetorotational Instability in Proto-Neutron Stars
Youhei Masada, Takayoshi Sano, Kazunari Shibata
Neutrino radiation takes a major role in the momentum, heat, and lepton transports in proto-neutron stars (PNSs). These diffusive processes affect the growth of magnetorotational i…
Nonaxisymmetric Magnetorotational Instability in Proto-Neutron Stars
Youhei Masada, Takayoshi Sano, Hideaki Takabe
We investigate the stability of differentially rotating proto-neutron stars (PNSs) with a toroidal magnetic field. Stability criteria for nonaxisymmetric MHD instabilities are deri…
Self-Sustained Ionization and Vanishing Dead Zones in Protoplanetary Disks
Shu-ichiro Inutsuka, Takayoshi Sano
We analyze the ionization state of the magnetohydrodynamically turbulent protoplanetary disks and propose a new mechanism of sustaining ionization. First, we show that in the quasi…
Angular Momentum Transport by MHD Turbulence in Accretion Disks: Gas Pressure Dependence of the Saturation Level of the Magnetorotational Instability
Takayoshi Sano, Shu-ichiro Inutsuka, Neal J. Turner +1
The saturation level of the magnetorotational instability (MRI) is investigated using three-dimensional MHD simulations. The shearing box approximation is adopted and the vertical…