Related papers: A Unified Computational Model for Solar and Stella…
We address the problem of particle acceleration in solar flares by fast modes which may be excited during the reconnection and undergo cascade and are subjected to damping. We extend the calculations beyond quasilinear approximation and…
There is observational evidence showing that stellar and solar flares occur in a similar circumstance, although the former are usually much more energetic. It is expected that the bombardment by high energy electrons is one of the chief…
Coronal mass ejections (CMEs) and eruptive flares (EFs) are the most energetic explosions in the solar system. Their underlying origin is the free energy that builds up slowly in the sheared magnetic field of a filament channel. We report…
A forward model is described in which we synthesize spectra from an ab-initio 3D MHD simulation of an outer stellar atmosphere, where the coronal heating is based on braiding of magnetic flux due to photospheric footpoint motions. We…
We establish a classification scheme for stochastic acceleration models involving low-frequency plasma turbulence in a strongly magnetized plasma. This classification takes into account both the properties of the accelerating…
The magnetic breakout model explains a variety of solar eruptions, ranging from small-scale jets to large-scale coronal mass ejections (CMEs). Most of our previous studies are focused on jets and CMEs in single null-point topologies. Here,…
Recent discoveries have revealed exoplanets orbiting young Sun-like stars, offering a window into the early solar system. These young stars frequently produce extreme magnetic explosions known as superflares, roughly once a day, potentially…
Context. Multi-dimensional solar flare simulations have not yet included detailed analysis of the lower atmospheric responses such as down-flowing chromospheric compressions and chromospheric evaporation processes. Aims. We present an…
Stellar flare events are critical observational samples for astronomical research; however, recorded flare events remain limited. Stellar flare forecasting can provide additional flare event samples to support research efforts. Despite this…
A model is presented for generation of fast solar wind in coronal holes, relying on heating that is dominated by turbulent dissipation of MHD fluctuations transported upwards in the solar atmosphere. Scale-separated transport equations…
We investigate the triggering mechanisms of plasma eruptions in the solar atmosphere due to interactions between emerging flux and coronal arcade fields by using two-dimensional MHD simulations. We perform parameter surveys with respect to…
Winds from massive stars have velocities of 1000 km/s or more, and produce hot, high pressure gas when they shock. We develop a theory for the evolution of bubbles driven by the collective winds from star clusters early in their lifetimes,…
EUV imaging observations from several space missions (SOHO/EIT, TRACE, and SDO/AIA) have revealed a presence of propagating intensity disturbances in solar coronal loops. These disturbances are typically interpreted as slow magnetoacoustic…
M dwarfs are known to flare on timescales from minutes to hours, with flux increases of several magnitudes in the blue/near-UV. These frequent, powerful events, which are caused by magnetic reconnection, will have a strong observational…
During solar flares, a large fraction of the released magnetic energy is carried by energetic electrons that transfer and deposit energy in the Sun's atmosphere. Electron transport is often approximated by a cold thick-target model (CTTM),…
We investigate gamma-ray emission in the impulsive phase of solar flares and the detectability of non-thermal signatures from protostellar flares. Energetic solar flares emit high-energy gamma rays of GeV energies, but their production…
Solar flares stem from the reconnection of twisted magnetic field lines in the solar photosphere. The energy and waiting time distributions of these events follow complex patterns that have been carefully considered in the past and that…
Sunquakes observed in the form of expanding wave ripples on the surface of the Sun during solar flares represent packets of acoustic waves excited by flare impacts and traveling through the solar interior. The excitation impacts strongly…
We study the temporal evolution of the Na I D1 line profiles in the M3.9 flare SOL2014-06-11T21:03 UT, using high spectral resolution observations obtained with the IBIS instrument on the Dunn Solar Telescope combined with radiative…
To predict line emission in the solar atmosphere requires models which are fundamentally different depending on whether the emission is from the chromosphere or the corona. At some point between the two regions, there must be a change…