Related papers: Evolution of twist-shear and dip-shear during X-cl…
Rapid and stepwise changes of the magnetic field are often observed during flares but cannot be explained by models yet. Using a 45 min sequence of SDO/HMI 135 s fast-cadence vector magnetograms of the X1 flare on 2014-03-29 we construct,…
A magnetic power spectral analysis is performed on 53 solar active regions, observed from August 2011 to July 2012. Magnetic field data obtained from the Helioseismic and Magnetic Imager, inverted as Active Region Patches, are used to study…
In the present work we study Hinode/EIS observations of an active region taken before, during and after a small C2.0 flare in order to monitor the evolution of the magnetic field evolution and its relation to the flare event. We find that…
This work is a continuation of Paper I [Sharykin et al., 2018] devoted to analysis of nonthermal electron dynamics and plasma heating in the confined M1.2 class solar flare SOL2015-03-15T22:43 revealing energy release in the highly sheared…
We apply a data-driven MHD model to investigate the three-dimensional (3D) magnetic field of NOAA active region (AR) 11117 around the time of a C-class confined flare occurred on 2010 October 25. The MHD model, based on the spacetime…
Magnetic flux ropes are the centerpiece of solar eruptions. Direct measurements for the magnetic field of flux ropes are crucial for understanding the triggering and energy release processes, yet they remain heretofore elusive. Here we…
We investigate the occurrence of slipping magnetic reconnection, chromospheric evaporation, and coronal loop dynamics in the 2014 September 10 X-class flare. The slipping reconnection is found to be present throughout the flare from its…
With machine learning entering into the awareness of the heliophysics community, solar flare prediction has become a topic of increased interest. Although machine learning models have advanced with each successive publication, the input…
Magnetic reconnection, a fundamentally important process in many aspects of astrophysics, is believed to be initiated by the tearing instability of an electric current sheet, a region where magnetic field abruptly changes direction and…
Flare ribbons are always dynamic, and sometimes sweep across sunspots. Examining 588 (513 M-class and 75 X-class) flare events observed by Transition Region and Coronal Explorer (TRACE) satellite and Hinode Solar Optical Telescope (SOT)…
We report a solar jet phenomenon associated with successive flares on November 10th 2014. These explosive events were involved with the satellite spots' emergence around a delta-type sunspot in the decaying active region NOAA 12205. The…
We analyze the spatial and temporal variations of the abrupt photospheric magnetic changes associated with six major flares using 12-minute, 0.5-arcsec vector magnetograms from NASA's Helioseismic and Magnetic Imager instrument (HMI) on the…
Recent observations of giant flares from soft gamma-ray repeaters have exhibited multiple 25-150 Hz oscillations. Frequencies in this range are expected for toroidal shear waves in a neutron star (NS) crust, lending support to Duncan's…
Some types of solar flares are observed in X-shaped quadrupolar field configuration. To understand the magnetic energy storage in such a region, we studied non-potential field formation in an X-shaped quadrupolar field region formed in the…
Current helicity and twist of solar magnetic fields are important quantities to characterize the dynamo mechanism working in the convection zone of the Sun. We have carried out a statistical study on the current helicity of solar active…
Magnetohydrodynamic (MHD) plasma turbulence is believed to play a vital role in the production of energetic electrons during solar flares and the non-thermal broadening of spectral lines is a key sign of this turbulence. Here, we determine…
The occurrence of X-class solar flares and their potential impact on the space weather often receive great attention than other flares. But predicting when and where an X-class flare will occur is still a challenge. With the…
We analyze the magnetic evolution of solar active region (AR) NOAA 11476 that, between 9 and 10 May 2012, produced a series of surge-type eruptions accompanied by GOES X-ray class M flares. Using force-free models of the AR coronal…
We measure the horizontal subsurface flow in a fast emerging active region (NOAA 11158) using the ring-diagram technique and the HMI high-spatial resolution Dopplergrams. This active region had a complex magnetic structure and displayed…
We analyze 152 large confined flares (GOES class $\geq$M1.0 and $\leq$$45^{\circ}$ from disk center) during 2010$-$2019, and classify them into two types according to the criterion taken from the work of Li et al. (2019). "Type I" flares…