Related papers: Heating and cooling at a coronal magnetic null
The bulk of solar coronal radiative loss consists of soft X-ray emission from quasi-static loops at the cores of Active Regions. In order to develop diagnostics for determining the heating mechanism of these loops from observations by…
We construct a simple model for a magnetic reconnection heated corona above a thin accretion disk in AGNs and Galactic black hole candidates(GBHCs). The basic assumptions are that (1) the magnetic reconnection heat is cooled down…
According to conventional wisdom, a system placed in an environment with a different temperature tends to relax to the temperature of the latter, mediated by the flows of heat and/or matter that are set solely by the temperature difference.…
Coronal rain consists of cool and dense plasma condensations formed in coronal loops as a result of thermal instability. Previous numerical simulations of thermal instability and coronal rain formation have relied on artificially adding a…
The connection between nuclear fusion in the Sun's core and solar irradiance is obscured among other things by uncertainty over the mechanism of coronal heating. Data for solar wind density and velocity, sunspot number, and EUV flux suggest…
The complex time-dependent heat and electromagnetic energy transfer in a new type of cooling system is analyzed. The system consists of a cold body, a Peltier element and an electric circuit containing an inductor with controllable…
Cool, dense material is frequently observed to permeate the hot, tenuous solar corona in the form of prominences, spicules and coronal rain. Both the cool material and surrounding corona exist at temperatures that are effectively thermally…
Coronal loops, constituting the basic building blocks of the active Sun, serve as primary targets to help understand the mechanisms responsible for maintaining multi-million Kelvin temperatures in the solar and stellar coronae. Despite…
Observations of the coronae of the Sun and of solar-like stars provide complementary information to advance our understanding of stellar magnetic activity, and of the processes leading to the heating of their outer atmospheres. While solar…
The temperature of the solar atmosphere increases from thousands to millions of degrees moving from the lower layer (chromosphere) to the outermost one (corona), while the density drops accordingly. The mechanism behind this phenomenon,…
Magnetic fields permeate the entire solar atmosphere weaving an extremely complex pattern on both local and global scales. In order to understand the nature of this tangled web of magnetic fields, its magnetic skeleton, which forms the…
The heating of the solar corona is likely to be due to reconnection of the highly complex magnetic field that threads throughout its volume. We have run a numerical experiment of an elementary interaction between the magnetic field of two…
The existence of the million-degree corona above the cooler photosphere is an unsolved problem in astrophysics. Detailed study of quiescent corona that exists regardless of the phase of the solar cycle may provide fruitful hints towards…
[..] The change in the magnetic configuration due to the increase/decrease of electric current for different force-free models (potential, linear and nonlinear force-free fields) has never been studied in detail before. Here we focus…
Numerical MHD simulations of 3D reconnection events in the solar corona have improved enormously over the last few years, not only in resolution, but also in their complexity, enabling more and more realistic modeling. Various ways to…
A crucial assumption in the conventional description of thermal conduction is the existence of local thermal equilibrium. We test this assumption in two simple models of heat conduction. Our first model is a linear chain of planar spins…
We study the unitary time evolution of a simple quantum Hamiltonian describing a heat engine coupled to two heat baths. The engine is modeled as a three-level system. Each heat bath consists of a single harmonic oscillator. The engine is…
The X-ray emission from the Sun reveals a very dynamic hot atmosphere, the corona, which is characterized by a complex morphology and broad range of timescales of variability and spatial structuring. The solar magnetic fields play a…
Radiative cooling is an important ingredient in hydrodynamical models involving evolution of high temperature plasmas. Unfortunately, calculating an accurate cooling coefficient generally requires the solution of over a hundred differential…
Current sheets are essential for energy dissipation in the solar corona, in particular by enabling magnetic reconnection. Unfortunately, sufficiently thin current sheets cannot be resolved observationally and the theory of their formation…