Related papers: Thermodynamic Evolution of Solar Flare Supra-arcad…

Particle acceleration in solar flares remains an outstanding problem in solar physics. It is yet unclear which of the acceleration mechanisms dominates and how exactly is the excessive magnetic energy transferred to the nonthermal and other…

Downflows on the solar surface are suspected to play a major role in the dynamics of the convection zone. We investigate the existence of the long-lasting downflows whose effects influence the interior of the Sun and the outer layers. We…

A subclass of early impulsive solar flares, cold flares, was proposed to represent a clean case, where the release of the free magnetic energy (almost) entirely goes to acceleration of the nonthermal electrons, while the observed thermal…

Some of local sources of the slow solar wind can be associated with spectroscopically detected plasma outflows at edges of active regions accompanied with specific signatures in the inner corona. The EUV telescopes (e.g. SPIRIT/CORONAS-F,…

Without any doubt solar flaring loops possess a multi-thread internal structure that is poorly resolved and there are no means to observe heating episodes and thermodynamic evolution of the individual threads. These limitations cause…

Spectroscopic observations of the emission lines formed in the solar transition region (TR) commonly show persistent downflows of the order of 10--15 km/s. The cause of such downflows, however, is still not fully clear and has remained a…

We explore the spatio-temporal evolution of solar flares by fitting a radial expansion model $r(t)$ that consists of an exponentially growing acceleration phase, followed by a deceleration phase that is parameterized by the generalized…

Solar flares strongly affect the Sun's atmosphere as well as the Earth's environment. Quantifying the maximum possible energy of solar flares of the present-day Sun, if any, is thus a key question in heliophysics. The largest solar flares…

SDO/EVE provides rich information of the thermodynamic processes of solar activities, particularly of solar flares. Here, we develop a method to construct thermodynamic spectrum (TDS) charts based on the EVE spectral lines. This tool could…

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…

We analyse the spatial distribution and vertical stratification of the physical parameters of the solar atmosphere when an X-class flare occurs. We made use of observations acquired by the Interferometric Bidimensional Spectropolarimeter…

Understanding how energy is released in flares is one of the central problems of solar and stellar astrophysics. Observations of high temperature flare plasma hold many potential clues as to the nature of this energy release. It is clear,…

Solar flares typically have an impulsive phase that followed by a gradual phase as best seen in soft X-ray emissions. A recent discovery based on the EUV Variability Experiment (EVE) observations onboard the Solar Dynamics Observatory (SDO)…

Two kinds of processes could occur during the flare decay phase: processes of energy release or processes of energy relaxation. Quasi-periodic pulsations (QPPs) of the broadband emission are a good tool for the verification of mechanisms.…

The emergence and magnetic evolution of solar active regions (ARs) of beta-gamma-delta type, which are known to be highly flare-productive, were studied with the SOHO/MDI data in Cycle 23. We selected 31 ARs that can be observed from their…

Solar flares are transient yet dramatic events in the atmosphere of the Sun, during which a vast amount of magnetic energy is liberated. This energy is subsequently transported through the solar atmosphere or into the heliosphere, and…

Recent observations and simulations indicate that solar flares undergo extremely complex three-dimensional (3D) evolution, making 3D particle transport models essential for understanding electron acceleration and interpreting flare…

Spectroscopic observations with the EUV Imaging Spectrometer (EIS) on Hinode have revealed large areas of high speed outflows at the periphery of many solar active regions. These outflows are of interest because they may connect to the…

Solar flares are sudden and violent releases of magnetic energy in the solar atmosphere that can be divided in eruptive flares, when plasma is ejected from the solar atmosphere, resulting in a coronal mass ejection (CME), and confined…

Arcades of flare loops form as a consequence of magnetic reconnection powering solar flares and eruptions. We analyse the morphology and evolution of flare arcades that formed during five well-known eruptive flares. We show that the arcades…