相关论文: A nanoflare model of quiet Sun EUV emission
Nanoflares, the basic unit of impulsive energy release may produce much of the solar background emission. Extrapolation of the energy frequency distribution of observed microflares, which follows a power law to lower energies can give an…
The content of coronal material in the quiet Sun is not constant as soft X-ray and high-temperature EUV line observations have shown. New material, probably heated and evaporated from the chromosphere is occasionally injected even in the…
The energy input into the lower solar corona by flare evaporation events has been modeled according to the available observations for quiet regions. The question is addressed whether such heating events can provide the observed average…
Recent imaging observations of EUV line emissions have shown evidence for frequent flare-like events in a majority of the pixels in quiet regions of the solar corona. The changes in coronal emission measure indicate impulsive heating of new…
A ubiquitous presence of weak energy releases is one of the most promising hypotheses to explain coronal heating, referred to as the nanoflare hypothesis. The accelerated electrons associated with such weak heating events are also expected…
The quiet solar corona consists of myriads of loop-like features, with magnetic fields originating from network and internetwork regions on the solar surface. The continuous interaction between these different magnetic patches leads to…
X-ray observations of the Sun led Eugene Parker to propose nanoflares as the basic energy-release units that heat the solar corona. Decades later, Solar Orbiter's Extreme Ultraviolet Imager (HRIEUV), operating halfway between Earth and the…
Context. Nanoflares are small impulsive bursts of energy that blend with and possibly make up much of the solar background emission. Determining their frequency and energy input is central to understanding the heating of the solar corona.…
Nanoflares in quiet-Sun regions during solar cycle 24 are studied with the best available plasma diagnostics to derive their energy distribution and contribution to coronal heating during different levels of solar activity. Extreme…
Magnetic energy is required to heat the corona, the outer atmosphere of the Sun, to millions of degrees. We study the nature of the magnetic energy source that is probably responsible for the brightening of coronal loops driven by…
This letter explores the relevance of nanoflare based models for heating the quiet sun corona. Using metrewave data from the Murchison Widefield Array, we present the first successful detection of impulsive emissions down to flux densities…
Microflares are small dynamic signatures observed in X-ray and extreme-ultraviolet channels. Because of their impulsive emission enhancements and wide distribution, they are thought to be closely related to coronal heating. By using the…
Recently nonthermal radio transients from the quiet sun have been discovered and it has been hypothesised using rough calculations that they might be important for coronal heating. It is well realized that energy calculations using coherent…
Flare frequency distributions represent a key approach to addressing one of the largest problems in solar and stellar physics: determining the mechanism that counter-intuitively heats coronae to temperatures that are orders of magnitude…
To explain the high temperature of the corona, much attention has been paid to the distribution of energy in dissipation events. Indeed, if the event energy distribution is steep enough, the smallest, unobservable events could be the…
All theories that attempt to explain the heating of the high temperature plasma observed in the solar corona are based on short bursts of energy. The intensities and velocities measured in the cores of quiescent active regions, however, can…
Brightenings observed in the solar extreme-ultraviolet (EUV) images are generally interpreted as signatures of micro- or nanoflares occurring at the transition region or coronal temperatures. Recent observations with the Extreme Ultraviolet…
We investigate the morphology and temporal variability of a quiet Sun network region in different solar layers. The emission in several EUV spectral lines through both raster and slot time series, recorded by EIS/Hinode is studied along…
To understand the mechanism of coronal heating, it is crucial to derive the contribution of small-scale flares, the so-called nanoflares, to the heating up of the solar corona. To date, several studies have tried to derive the occurrence…
The content of hot material in the corona is not constant. Soft X-ray and high-temperature EUV line observations show that new material, apparently heated and evaporated from the chromosphere, is frequently injected into the corona both in…