相关论文: On mesogranulation, network formation and supergra…
Stellar surface magnetoconvection (granulation) creates asymmetries in the observed stellar absorption lines that can subsequently manifest themselves as spurious radial velocities shifts. In turn, this can then mask the Doppler-reflex…
We study structure, eigenvalue spectra and diffusion dynamics in a wide class of networks with subgraphs (modules) at mesoscopic scale. The networks are grown within the model with three parameters controlling the number of modules, their…
We present results from a high-resolution and large-scale hybrid (fluid electrons and particle-in-cell protons) two-dimensional numerical simulation of decaying turbulence. Two distinct spectral regions (separated by a smooth break at…
The operation of the solar global dynamo appears to involve many dynamical elements. Self-consistent MHD simulations which realistically incorporate all of these processes are not yet computationally feasible, though some elements can now…
The large-scale convection in the Sun known as supergranulation is manifested as a network structure on the solar surface. The network cells have an average lifetime of 24 hr, a size of about 30 Mm, and a lane width of about 6 Mm. We have…
A proxy for horizontal electric currents in the solar photosphere was suggested. For a set of evolving active regions (ARs) observed with {\it Solar and Heliospheric Observatory (SOHO)} Michelson Doppler Imager (MDI) in the high resolution…
The solar photosphere provides us with a laboratory for understanding turbulence in a layer where the fundamental processes of transport vary rapidly and a strongly superadiabatic region lies very closely to a subadiabatic layer. Our tools…
Macroscopic gas motions are widespread throughout the solar atmosphere and shearing motions couple to the non--ideal effects, destabilising low frequency fluctuations in the medium. The origin of this non-ideal magnetohydrodynamic…
Understanding how granular materials respond to shear stress remains a central challenge in soft matter physics. We report direct observations of persistent granular convection in the bulk shear zones of spherical particle packings -- a…
A 50 min time series of one-dimensional slit-spectrograms, taken in quiet sun at disk center, observed at the German Vacuum Tower Telescope (Observatorio del Teide), was used to study the global and spatial variations of different line…
It is generally believed that sunspots are the emergent part of magnetic flux tubes in the solar interior. These tubes are created at the base of the convection zone and rise to the surface due to their magnetic buoyancy. The motion of…
Around our Sun, terrestrial planets did not grow beyond Earth in mass, while super-Earths are found to orbit approximately every other solar-like star. It remains unclear what divides these super-Earth systems from those that form…
Differences between observed and theoretical eigenfrequencies of the Sun have characteristics which identify them as arising predominantly from properties of the oscillations in the vicinity of the solar surface: in the super-adiabatic,…
Exploding granules have drawn renewed interest because of their interaction with the magnetic field. Especially the newly forming downflow lanes developing in their centre seem to be eligible candidates for the intensification of magnetic…
We apply the mathematical formalism of vector spherical harmonics decomposition to convective stellar velocity fields from multi-dimensional hydrodynamics simulations, and show that the resulting power spectra furnish a robust and stable…
Some preliminary processing results are presented for a dataset obtained with the Solar Optical Telescope on the Hinode satellite. The idea of the project is to record, nearly simultaneously, the full velocity and magnetic-field vectors in…
The atmosphere of the Sun is characterized by a complex interplay of competing physical processes: convection, radiation, conduction, and magnetic fields. The most obvious imprint of the solar convection and its overshooting in the low…
Observations of the solar photosphere show spatially-compact large-amplitude Doppler velocity events with short lifetimes. In data from the Imaging Magnetograph eXperiment (IMaX) on the first flight of the Sunrise balloon in 2009, events…
Magnetic element tracking is often used to study the transport and diffusion of the magnetic field on the solar photosphere. From the analysis of the displacement spectrum of these tracers, it has been recently agreed that a regime of…
Turbulent flows in the solar wind, large scale current sheets, multiple current sheets, and shock waves lead to the formation of environments in which a dense network of current sheets is established and sustains "turbulent reconnection".…