Related papers: A Cold Flare With Delayed Heating
The origin and radiation mechanisms of high energy emissions from pulsars have remained mysterious since their discovery. Here we report, based on a sample of 68 pulsars, observational connection of non-thermal X-ray emissions from pulsars…
We study the signatures of different coronal heating regimes on the differential emission measure (DEM) of multi-stranded coronal loops by means of hydrodynamic simulations. We consider heating either uniformly distributed along the loops…
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…
We model the Neupert effect that relates flare heating energy with the observed SXR emission. The traditional form of the Neupert effect refers to the correlation between the time-integrated HXR or microwave light curve and the SXR light…
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…
It is extremely difficult to simulate the details of coronal heating and also make meaningful predictions of the emitted radiation. Thus, testing realistic models with observations is a major challenge. Observational signatures of coronal…
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,…
In the present work we study the C8 flare occurred on September 26, 2000 at 19:49 UT and observed by the SOHO/SUMER spectrometer from the beginning of the impulsive phase to well beyond the disappearance in the X-rays. The emission first…
Solar flares are powerful particle accelerators, and in the accepted standard flare model most of the flare energy is transported from a coronal energy-release region by accelerated electrons which stop collisionally in the chromosphere,…
We investigate the heating of an erupting prominence and loops associated with a coronal mass ejection and X-class flare. The prominence is seen in absorption in EUV at the beginning of its eruption. Later the prominence changes to…
X-ray observations provide important and valuable insights into the acceleration and propagation of nonthermal electrons during solar flares. Improved X-ray spectral analysis requires a deeper understanding of the dynamics of energetic…
Non-thermal power-law distribution functions are ubiquitous in astrophysical, space, and laboratory kinetic plasmas, but their origin remains unclear. A related puzzle is the temperature inversion of the solar corona. We show that these…
We analyze and model an M1.0 flare observed by SDO/AIA and Hinode/EIS to investigate how flare loops are heated and evolve subsequently. The flare is composed of two distinctive loop systems observed in EUV images. The UV 1600 \AA emission…
Context. Observations of slow magnetoacoustic waves in solar coronal loops suggest that, in hot coronal plasma, heat conduction may be suppressed in comparison with the classical thermal transport model. Aims. We link this suppression with…
We present the results of 1D hydrodynamic simulations of coronal loops which are subject to nanoflares, caused by either in-situ thermal heating, or non-thermal electrons (NTE) beams. The synthesized intensity and Doppler shifts can be…
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…
Even in the absence of resolved flares, the corona is heated to several million degrees. However, despite its importance for the structure, dynamics, and evolution of the solar atmosphere, the origin of this heating remains poorly…
The expansion of hot electrons in flaring magnetic loops is crucial to understanding the dynamics of solar flares. In this paper we investigate, for the first time, the transport of hot electrons in a magnetic mirror field based on a 1-D…
We propose that non-thermal electrons are efficiently accelerated by first-order Fermi process at the fast shock, as a natural consequence of the new magnetohydrodynamic picture of the flaring region revealed with Yohkoh. An oblique fast…
The energy released during solar flares is believed to be stored in non-potential magnetic fields associated with electric currents flowing in the corona. While no measurements of coronal electric currents are presently available, maps of…