Related papers: Statistical Study of Plasmoids associated with pos…
The initiation phase of CMEs is a very important aspect of solar physics, as these phenomena ultimately drive space weather in the heliosphere. This phase is known to occur between the photosphere and low corona, where many models introduce…
We study the linear and nonlinear evolution of the tearing instability on thin current sheets by means of two-dimensional numerical simulations, within the framework of compressible, resistive magnetohydrodynamics. In particular we analyze…
An unexpected strong geomagnetic storm occurred on 2018 August 26, which was caused by a slow coronal mass ejection (CME) from a gradual eruption of a large quiet-region filament. We investigate the eruption and propagation characteristics…
With increasing solar activity since 2010, many flares from the backside of the Sun have been observed by the Extreme Ultraviolet Imager (EUVI) on either of the twin STEREO spacecraft. Our objective is to estimate their X-ray peak fluxes…
Kink-like flapping motions of current sheets are commonly observed in the magnetotail. Such oscillations have periods of a few minutes down to a few seconds and they propagate toward the flanks of the plasma sheet. Here, we report a…
On 8 November 2013 a halo-type coronal mass ejection (CME) was observed, together with flares and type II radio bursts, but the association between the flares, radio bursts, and the CME was not clear. Our aim is to identify the origin of…
We analyze the structure and evolution of ribbons from the M7.3 SOL2014-04-18T13 flare using ultraviolet (UV) images from IRIS and SDO/AIA, magnetic data from SDO/HMI, hard X-ray (HXR) images from RHESSI, and light curves from Fermi/GBM, in…
On 7 January 2014 an X1.2 flare and CME with a radial speed $\approx$2500 km s$^{-1}$ was observed from near an active region close to disk center. This led many forecasters to estimate a rapid arrival at Earth ($\approx$36 hours) and…
We report a new, plasmoid-fed scenario for the formation of an eruptive prominence (PF$^2$), involving reconnection and condensation. We use grid-adaptive resistive two-and-a-half-dimensional magnetohydrodynamic (MHD) simulations in a…
Using the potential of two unprecedented missions, STEREO and RHESSI, we study three well observed fast CMEs that occurred close to the limb together with their associated high energy flare emissions in terms of RHESSI HXR spectra and flux…
It is difficult to measure the true speed of Earth-directed CMEs from a coronagraph located along the Sun-Earth line because of the occulting disk. However, the expansion speed (the speed with which the CME appears to spread in the sky…
We present an event observed by Parker Solar Probe at $\sim$0.2 au on March 2, 2022 in which imaging and \emph{in situ} measurements coincide. During this event, PSP passed through structures on the flank of a streamer blowout CME including…
The shape and dynamics of coronal mass ejections (CMEs) vary significantly based on the instrument and wavelength used. This has led to significant debate about the proper definitions of CME/shock fronts, pile-up/compression regions, and…
Eruptive phenomena such as plasmoid ejections or jets are an important feature of solar activity with the potential for improving our understanding of the dynamics of the solar atmosphere. Such ejections are often thought to be signatures…
In the standard model, magnetic reconnection at a vertical current sheet above the flare arcade is key to explaining many aspects of solar eruptions. The supra-arcade region is where the vertical current sheet is supposedly located, and…
On 2014 October 30, a band-splitted type II radio burst associated with a coronal mass ejection (CME) observed by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO) occurred over the southeast limb of the…
Stellar flares are characterized by sudden enhancement of electromagnetic radiation in stellar atmospheres. So far much of our understanding of stellar flares comes from photometric observations, from which plasma motions in flare regions…
We present a new method to extract the three-dimensional electron density profile and density compression ratio of shock fronts associated with Coronal Mass Ejections (CMEs) observed in white light coronagraph images. We demonstrate the…
We study the 17 January 2010 flare-CME-wave event by using STEREO/SECCHI EUVI and COR1 data. The observational study is combined with an analytic model which simulates the evolution of the coronal-wave phenomenon associated with the event.…
We study the origin of a CME-related shock within the LASCO C3 field-of-view (FOV). A shock originates, when a CME body velocity on its axis surpasses the total velocity $V_A + V_{SW}$, where $V_A$ is the Alfv\'en velocity, $V_{SW}$ is the…