Related papers: Hard X-Ray Constraints on Small-Scale Coronal Heat…
We present the results of an analysis of hard X-ray observations of the C2.7 solar flare detected by the RT-2 Experiment onboard the Coronas - Photon satellite. We detect hard X-ray pulsations at periods of ~12 s and ~15 s. We find a…
Solar flares are sudden energy release events in the solar corona, resulting from magnetic reconnection, that accelerates particles and heats the ambient plasma. During a flare, there are often multiple, temporally and spatially separated…
During a solar flare, electrons are accelerated to non-thermal energies as a result of magnetic reconnection. These electrons then propagate upwards and downwards from the energy release site along magnetic field lines and produce radio and…
Fitting the thermal X-ray spectra of neutron stars (NSs) in quiescent X-ray binaries can constrain the masses and radii of NSs. The effect of undetected hot spots on the spectrum, and thus on the inferred NS mass and radius, has not yet…
We investigate the relative timing between hard X-ray (HXR) peaks and structures in metric and decimetric radio emissions of solar flares using data from the RHESSI and Phoenix-2 instruments. The radio events under consideration are…
Using the observations from the Atmospheric Imaging Assembly (AIA) and Helioseismic and Magnetic Imager (HMI) aboard the Solar Dynamics Observatory (SDO), we investigate six X-class and twenty-nine M-class flares occurring in solar active…
We present the results from a coordinated XMM-Newton $+$ NuSTAR observation of the Seyfert 1 Galaxy ESO 511$-$G030. With this joint monitoring programme, we conduct a detailed variability and spectral analysis. The source remained in a low…
Long-lasting, intense, stellar X-ray flares may approach conditions of breaking magnetic confinement and evolving in open space. We explore this hypothesis with hydrodynamic simulations of flares occurring in a non-confined corona: model…
The solar corona is full of dynamic phenomena, e.g., solar flares, micro flares in active regions, jets in coronal holes and in the polar regions, X-ray bright points in quiet regions, etc. They are accompanied by interesting physical…
We present the first results using the Reuven Ramaty High-Energy Solar Spectroscopic Imager, RHESSI, to observe solar X-ray emission not associated with active regions, sunspots or flares (the quiet Sun). Using a newly developed chopping…
Solar and stellar flares are powerful events which produce intense radiation across the electromagnetic spectrum. Multiwavelength observations are highly important for understanding the nature of flares, because different flare-related…
Recent progress in solar Hard X-ray (HXR) observations with RHESSI data and methods for spectral inversion allow us to study model-independent mean electron flux spectra in solar flares. We report several hard X-ray events observed by…
The solar corona is much hotter than the photosphere and chromosphere, but the physical mechanism responsible for heating the coronal plasma remains unidentified yet. The thermal microwave emission, which is produced in strong magnetic…
The NuSTAR observatory, with its high sensitivity in hard X-rays, has enabled detailed broadband modeling of the X-ray spectra of Active Galactic Nuclei (AGN), thereby allowing constraints to be placed on the high-energy cutoff of the X-ray…
We investigate the thermal, kinematic and magnetic structure of small-scale heating events in an emerging flux region (EFR). We use high-resolution multi-line observations (including Ca II 8542~\AA, Ca II K, and Fe I 6301~\AA line pair) of…
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.…
Solar flares are efficient particle accelerators with a large fraction of released magnetic energy (10-50%) converted into energetic particles such as hard X-ray producing electrons. This energy transfer process is not well constrained,…
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…
Coronal X-ray sources (CXSs) are phenomenon very often occurring in solar flares regardless of a flare size, duration or power. The nature of the sources was difficult to uncover for many years. It seems that at last, combining data from…
It has been suggested that the hot plasma of the solar corona comes primarily from impulsive heating events, or nanoflares, that occur in the lower atmosphere, either in the upper part of the ordinary chromosphere or at the tips of type II…