106 citations · 674 across the 25 of their papers we have counts for
25 papers
Solar horizontal flow evaluation using neural network and numerical simulation with snapshot data
Hiroyuki Masaki, Hideyuki Hotta, Yukio Katsukawa +1
We suggest a method that evaluates the horizontal velocity in the solar photosphere with easily observable values using a combination of neural network and radiative magnetohydrody…
Scale-dependent analysis of angular momentum flux in high-resolution magnetohydrodynamic simulations for solar differential rotation
K. Mori, H. Hotta
In this work, we systematically investigate the scale-dependent angular momentum flux by analysing high-resolution three-dimensional magnetohydrodynamic simulations in which the so…
Dynamics of solar large-scale flows
Hideyuki Hotta, Yuto Bekki, Laurent Gizon +2
The Sun's axisymmetric large-scale flows, differential rotation and meridional circulation, are thought to be maintained by the influence of rotation on the thermal-convective moti…
A Comprehensive Simulation of Solar Wind Formation from the Solar Interior: Significant Cross-field Energy Transport by Interchange Reconnection near the Sun
H. Iijima, T. Matsumoto, H. Hotta +1
The physical connection between thermal convection in the solar interior and the solar wind remains unclear due to their significant scale separation. Using an extended version of…
Turbulent convection as a significant hidden provider of magnetic helicity in solar eruptions
Shin Toriumi, Hideyuki Hotta, Kanya Kusano
Solar flares and coronal mass ejections, the primary space weather disturbances affecting the entire heliosphere and near-Earth environment, mainly emanate from sunspot regions har…
Investigation of the dependence of angular momentum transport on spatial scales for construction of differential rotation
K. Mori, H. Hotta
We investigate the dependence of the angular momentum transport (AMT) on the spatial scales with numerical simulation of solar-like stars. It is thought that turbulence has an esse…
Impact of subsurface convective flows on the formation of sunspot magnetic field and energy build-up
Takafumi Kaneko, Hideyuki Hotta, Shin Toriumi +1
Strong solar flares occur in -spots characterized by the opposite-polarity magnetic fluxes in a single penumbra. Sunspot formation via flux emergence from the convection zone to…
Mean-field analysis on large-scale magnetic fields at high Reynolds numbers
Ryota Shimada, Hideyuki Hotta, Takaaki Yokoyama
Solar magnetic fields comprise an 11-year activity cycle, represented by the number of sunspots. The maintenance of such a solar magnetic field can be attributed to fluid motion in…
Generation solar-like differential rotation
H. Hotta, K. Kusano, R. Shimada
We analyze the simulation result shown in Hotta & Kusano, 2021 in which the solar-like differential rotation is reproduced. The Sun is rotating differentially with the fast equator…
Solar differential rotation reproduced with high-resolution simulation
H. Hotta, K. Kusano
The Sun rotates differentially with a fast equator and slow pole. Convection in the solar interior is thought to maintain the differential rotation. However, although many numerica…
Relationship between magnetic field properties and statistical flow using numerical simulation and magnetic feature tracking on solar photosphere
K. Takahata, H. Hotta, Y. Iida +1
We perform radiative magnetohydrodynamic calculations for the solar quiet region to investigate the dependence of statistical flow on magnetic properties and the three-dimensional…
Formation of super-strong horizontal magnetic field in delta-type sunspot in radiation magnetohydrodynamic simulations
H. Hotta, S. Toriumi
We perform a series of radiative magnetohydrodynamic simulations to understand the amplification mechanism of the exceptionally strong horizontal magnetic field in delta-type sunsp…
On rising magnetic flux tube and formation of sunspots in a deep domain
H. Hotta, H. Iijima
We investigate the rising flux tube and the formation of sunspots in an unprecedentedly deep computational domain that covers the whole convection zone with a radiative magnetohydr…
Spontaneous Generation of delta-sunspots in Convective Magnetohydrodynamic Simulation of Magnetic Flux Emergence
Shin Toriumi, Hideyuki Hotta
Observations reveal that strong solar flares and coronal mass ejections tend to occur in complex active regions characterized by delta-sunspots, spot rotation, sheared polarity inv…
Semi-conservative reduced speed of sound technique for low Mach number flows with large density variations
H. Iijima, H. Hotta, S. Imada
The reduced speed of sound technique (RSST) has been used for efficient simulation of low Mach number flows in solar and stellar convection zones. The basic RSST equations are hype…
Asteroseismic detection of latitudinal differential rotation in 13 Sun-like stars
O. Benomar, M. Bazot, M. B. Nielsen +7
The differentially rotating outer layers of stars are thought to play a role in driving their magnetic activity, but the underlying mechanisms that generate and sustain differentia…
Breaking Taylor-Proudman balance by magnetic field in stellar convection zone
H. Hotta
We carry out high-resolution calculations for the stellar convection zone. The main purpose of this study is to investigate the effect of a small-scale dynamo on the differential r…
Sunspot Drawings by Japanese Official Astronomers in 1749-1750
Hisashi Hayakawa, Kiyomi Iwahashi, Masashi Fujiyama +7
Sunspot observations with telescopes in 18th century were carried out in Japan as well. One of these sunspot observations is recorded in an account called Sansaizusetsu narabini Ka…
Spatial inhomogeneity of kinetic and magnetic dissipations in thermal convection
H. Hotta
We investigate the inhomogeneity of kinetic and magnetic dissipations in thermal convection using high-resolution calculations. In statistically steady turbulence, the injected and…
Solar overshoot region and small-scale dynamo with realistic energy flux
H. Hotta
We carry out high resolution calculations of the solar overshoot region with unprecedentedly realistic parameters, especially the small energy flux compared with ,…
High-resolution calculations of the solar global convection with the reduced speed of sound technique: I. The structure of the convection and the magnetic field without the rotation
H. Hotta, M. Rempel, T. Yokoyama
We carry out non-rotating high-resolution calculations of the solar global convection, which resolve convective scales of less than 10 Mm. To cope with the low Mach number conditio…
Magnetic field intensification by three-dimensional explosion process
H. Hotta, M. Rempel, T. Yokoyama
We investigate an intensification mechanism for the magnetic field near the base of the solar convection zone that does not rely on differential rotation. Such mechanism in additio…
Estimation of turbulent diffusivity with direct numerical simulation of stellar convection
H. Hotta, Y. Iida, T. Yokoyama
We investigate the value of horizontal turbulent diffusivity η by numerical calculation of thermal convection. In this study, we introduce a new method whereby the turbulent diffus…
Numerical Calculation of Convection with Reduced Speed of Sound Technique
H. Hotta, M. Rempel, T. Yokoyama +2
Context. The anelastic approximation is often adopted in numerical calculation with low Mach number, such as stellar internal convection. This approximation requires frequent globa…