相关论文: Chromospheric Dynamics and Line Formation
The overall structure and the fine structure of the solar photosphere outside active regions are largely understood, except possibly important roles of a turbulent near-surface dynamo at its bottom, internal gravity waves at its top, and…
Our knowledge of the heating mechanisms that are at work in the chromosphere of plage regions remains highly unconstrained from observational studies. The purpose of our study is to estimate the chromospheric heating terms from a plage…
The instability and nonlinear evolution of directional ocean waves is investigated numerically by means of simulations of the governing kinetic equation for narrow-band surface waves. Our simulation results reveal the onset of the…
Accurately assessing the balance between acoustic wave energy fluxes and radiative losses is critical for understanding how the solar chromosphere is thermally regulated. We investigate the energy balance in the chromosphere by comparing…
Modeling the variability of the solar spectral irradiance is a key factor for understanding the solar influence on the climate of the Earth. As a first step to calculating the solar spectral irradiance variations we reproduce the solar…
Changes in the atmospheric composition alter the magnitude and partitioning between the downward propagating solar and atmospheric longwave radiative fluxes heating the Earth's surface. These changes are computed by radiative transfer codes…
We calculate NLTE models of stellar winds of hot compact stars (central stars of planetary nebulae and subdwarf stars). The studied range of subdwarf parameters is selected to cover a large part of these stars. The models predict the wind…
Natural convection is usually complicated by additional factors such as rotation, shear, radiative transfer, compressibility and electromagnetic fields (in the case of electro-conductive fluids). It is shown, using results of numerical…
The complex spectropolarimetric patterns around strong chromospheric lines, the result of subtle spectroscopic and transport mechanisms, are sensitive, sometimes in unexpected ways, to the presence of magnetic fields in the chromosphere,…
Condensation and sublimation of water vapors (and CO2, CH4, N2O vapors also) in the Earth atmosphere must be accompanied by emission of latent heats on characteristic frequencies marked in absorption spectra. Calculated wave lengths…
We test our knowledge of the atomic opacity in the solar UV spectrum. Using the atomic data compiled in Paper I from modern, publicly available, databases, we perform calculations that are confronted with space-based observations of the…
We discuss the turbulent structure and dynamics of the upper solar convection zone using a 3D radiative hydrodynamic simulation model at 45 degrees latitude. The model reveals the self-formation of meridional flows, the leptocline, and the…
The distribution of temperature and emission measure in the stationary heated solar atmosphere was obtained for the limiting cases of slow and fast heating, when either the gas pressure or the concentration are constant throughout the layer…
We investigate how wave propagation is modified by the presence of heat sources and sinks, in the simple 1D, hydrodynamical case, including chromosphere and solar wind. We integrate the time-dependent hydrodynamic equations of the solar…
Recent irradiance measurements from numerous heliophysics and astrophysics missions including SDO, GOES, Kepler, TESS, Chandra, XMM-Newton, and NICER have provided critical input in understanding the physics of the most powerful transient…
The interface between the bright solar surface and the million-degree corona continues to hold the key to many unsolved problems in solar physics. Advances in instrumentation now allow us to observe the dynamic structures of the solar…
The correct interpretation of the large amount of complex data from next-generation (in particular, space-based) observational facilities requires a very strong theoretical underpinning. One can thus predict that in the near future the use…
We analyze a grid of radiative hydrodynamic simulations of solar flares to study the energy balance and response of the atmosphere to nonthermal electron beam heating. The appearance of chromospheric bubbles is one of the most notable…
The interpretation of water lines in red supergiant stellar atmospheres has been much debated over the past decade. The introduction of the so-called MOLspheres to account for near-infrared "extra" absorption has been controversial. We…
The quantum theory of polarized light allows one to model scattering in the solar atmosphere for inferring its properties. This powerful approach has revealed two key long-standing problems in solar physics: the puzzling dilemmas between…