Related papers: Transient Inverse-FIP Plasma Composition Evolution…
We have used Chandra to resolve the nearby 70 Oph (K0 V+K5 V) and 36 Oph (K1 V+K1 V) binary systems for the first time in X-rays. The LETG/HRC-S spectra of all four of these stars are presented and compared with an archival LETG spectrum of…
We outline and discuss a model for the enhanced abundances of trans-Fe elements in impulsive Solar Energetic Particle (SEP) events, where large mass dependent abundance enhancements are frequently seen. It comes about as a variation of the…
Using the H$\alpha$ observations from the New Vacuum Solar Telescope at Fuxian Solar Observatory, we focus on the fine structures of three confined flares and the issue why all the three flares are confined instead of eruptive. All the…
Here, we present numerical simulations of magnetic flux buoyantly rising from a granular convection zone into the low corona. We study the complex interaction of the magnetic field with the turbulent plasma. The model includes the radiative…
Low-mass ultrafast rotators show the typical signatures of magnetic activity and are known to produce flares, probably as a result of magnetic reconnection. As a consequence, the coronae of these stars exhibit very large X-ray luminosities…
We propose an in-situ formation model for inverse-polarity solar prominence and demonstrate it using self-consistent 2.5-dimensional magnetohydrodynamics simulations, including thermal conduction along magnetic fields and optically thin…
Our aim is to study the photospheric flux distribution of a twisted flux tube that emerges from the solar interior. We also report on the eruption of a new flux rope when the emerging tube rises into a pre-existing magnetic field in the…
Why the tenuous solar outer atmosphere, or corona, is much hotter than the underlying layers remains one of the greatest challenge for solar modeling. Detailed diagnostics of the coronal thermal structure come from extreme ultraviolet (EUV)…
Accurate forecasting of space weather requires knowledge of the source regions where solar energetic particles (SEP) and eruptive events originate. Recent work has linked several major SEP events in 2014, January, to specific features in…
We report X-ray spectroscopic results for four giant solar flares occurred on 2005 September 7 (X17.0), 2005 September 8 (X5.4), 2005 September 9 (X6.2), and 2006 December 5 (X9.0), obtained from Earth albedo data with the X-ray imaging…
We propose a magnetic confinement nuclear fusion mechanism for the evolution of a solar flare in solar atmosphere. The mechanism agree with two observed characteristics of explosive flares and coronal mass ejections (CMEs) that have proved…
We present an X-ray spectral analysis of four solar analogs with different ages and magnetic activity levels. We find largely different coronal compositions. The most active stars tend to show an ``Inverse First Ionization Potential''…
We analyze Chandra X-ray spectra of the M0 V+M0 V binary GJ 338. As quantified by X-ray surface flux, these are the most inactive M dwarfs ever observed with X-ray grating spectroscopy. We focus on measuring coronal abundances, in…
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…
Sun-as-a-star coronal plasma composition, derived from full-Sun spectra, and the F10.7 radio flux (2.8 GHz) have been shown to be highly correlated (r = 0.88) during solar cycle 24. However, this correlation becomes nonlinear during…
The spatiotemporal evolution of the field and plasma in the optical breakdown induced in the volume of transparent dielectric (fused silica) by the focused fs laser pulse is studied under condition of the so-called plasma-resonance-induced…
We examine spectropolarimetric data from the CoMP instrument, acquired during the evolution of the September 10th 2017 X8.2 solar flare on the western solar limb. CoMP captured linearly polarized light from two emission lines of Fe XIII at…
We present an analysis of the first connection mosaic made by the SPICE instrument on board of the ESA / NASA Solar Orbiter mission on March 2nd, 2022. The data will be used to map coronal composition that will be compared with in-situ…
During solar flares a tremendous amount of magnetic energy is released and transported through the Sun's atmosphere and out into the heliosphere. Despite over a century of study, many unresolved questions surrounding solar flares are still…
The last 60 years of space exploration have shown that the interplanetary medium is continually perturbed by a myriad of different solar winds and storms that transport solar material across the whole heliosphere. If there is a consensus on…