Zobrazeno 1 - 10
of 106
pro vyhledávání: '"Masada, Youhei"'
Publikováno v:
Spa. Sci. Rev. 219, 55 (2023)
Mean-field dynamo theory has important applications in solar physics and galactic magnetism. We discuss some of the many turbulence effects relevant to the generation of large-scale magnetic fields in the solar convection zone. The mean-field descrip
Externí odkaz:
http://arxiv.org/abs/2303.12425
Autor:
Masada, Youhei, Sano, Takayoshi
In a rigidly-rotating magnetohydrodynamic (MHD) system with convective turbulence, a large-scale dynamo, categorized as the $\alpha^2$-type, can be excited when the spin rate is large enough. In this paper, the rotational dependence of the $\alpha^2$
Externí odkaz:
http://arxiv.org/abs/2206.06566
Autor:
Ishikawa, Ryohtaroh T., Nakata, Motoki, Katsukawa, Yukio, Masada, Youhei, Riethmüller, Tino L.
Publikováno v:
A&A 658, A142 (2022)
The dynamics in the photosphere is governed by the multi-scale turbulent convection termed as granulation and supergranulation. It is important to derive 3-dimensional velocity vectors to understand the nature of the turbulent convection. However, it
Externí odkaz:
http://arxiv.org/abs/2111.12518
Plumes in a convective flow are considered to be relevant to the turbulent transport in convection. The effective mass, momentum, and heat transports in the convective turbulence are investigated in the framework of time--space double averaging proce
Externí odkaz:
http://arxiv.org/abs/2111.08921
To study properties of magneto-hydrodynamic (MHD) convection and resultant dynamo activities in proto-neutron stars (PNSs), we construct a "PNS in a box" simulation model with solving compressible MHD equation coupled with a nuclear equation of state
Externí odkaz:
http://arxiv.org/abs/2001.08452
Autor:
Matsumoto, Jin, Masada, Youhei
A cocoon is a by-product of a propagating jet that results from shock heating at the jet head. Herein, considering simultaneous cocoon formation, we study the stability of relativistic jets propagating through the uniform ambient medium. Using a simp
Externí odkaz:
http://arxiv.org/abs/1910.11578
Autor:
Kawanaka, Norita, Masada, Youhei
We investigate the stability of a neutrino-dominated accretion flow (NDAF), which is expected to be formed in the gravitational collapse of a massive star or the merger of a neutron star binary, based on the variable-$\alpha$ prescription. Recent mag
Externí odkaz:
http://arxiv.org/abs/1902.08624
Publikováno v:
Phys. Rev. D 98, 083018 (2018)
Macroscopic evolution of relativistic charged matter with chirality imbalance is described by the chiral magnetohydrodynamics (chiral MHD). One such astrophysical system is high-density lepton matter in core-collapse supernovae where the chirality im
Externí odkaz:
http://arxiv.org/abs/1805.10419
Autor:
Masada, Youhei, Sano, Takayoshi
We report the first successful simulation of spontaneous formation of surface magnetic structures from a large-scale dynamo by strongly-stratified thermal convection in Cartesian geometry. The large-scale dynamo observed in our strongly-stratified mo
Externí odkaz:
http://arxiv.org/abs/1604.05374
Effects of magnetic field on stellar differential rotation are studied by comparing magnetohydrodynamic (MHD) models and their hydrodynamic (HD) counterparts in the broad range of rotation rate and in varying initial rotation profile. Fully-compressi
Externí odkaz:
http://arxiv.org/abs/1504.01129