相关论文: Ca II 8542 \AA\ brightenings induced by a solar mi…

Ellerman bombs are transient brightenings of the extended wings of the solar Balmer lines in emerging active regions. We describe their properties in the ultraviolet lines sampled by the Interface Region Imaging Spectrograph (IRIS), using…

The IRIS Mg II k line serves as a very good tool to diagnose the heating processes in solar flares. Recent studies have shown that apart from the usual red asymmetries which are interpreted as the result of condensation downflows, this line…

Even in quiet areas underneath coronal holes the solar chromosphere contains ubiquitous heating events. They tend to be small scale and short lived, hence difficult to identify. Here we do not address their much-debated contribution to…

The forward fitting of solar flare observations with radiation-hydrodynamic simulations is a common technique for learning about energy deposition and atmospheric evolution during these explosive events. A frequent spectral line choice for…

Aims. The purpose of this investigation is to characterize the temporal evolution of an emerging flux region, the associated photospheric and chromospheric flow fields, and the properties of the accompanying arch filament system. Methods.…

Aim: To study the interaction of the solar chromosphere with the transition region, in particular active-region jets in the transition region and their relation to chromospheric fibrils. Methods: We carefully align image sequences taken…

We aim to find similarities and differences between microflares at coronal bright points found in quiet regions and coronal holes, and to study their relationship with large scale flares. Coronal bright points in quiet regions and in…

Spectroscopic observations covering the wavelength range 3600--4600\AA are presented for a large flare on the late type M dwarf AT Mic (dM4.5e). A procedure to estimate the physical parameters of the flaring plasma has been used which…

Solar filaments exist as stable structures for extended periods of time before many of them form the core of a CME. We examine the properties of an erupting filament on 2017 May 29--30 with high-resolution He I 10830 A and Halpha spectra…

We discuss observations of chromospheric evaporation for a complex flare that occurred on 9 March 2012 near 03:30 UT obtained from the Extreme-ultraviolet Imaging Spectrometer (EIS) on the Hinode spacecraft. This was a multiple event with a…

In the standard 2D model of eruption, the eruption of a magnetic flux rope is associated with magnetic reconnection occurring beneath it. However, in 3D, additional reconnection geometries are possible, in particular the AR-RF, where…

Solar chromospheric fibrils, as observed in the core of strong chromospheric spectral lines, extend from photospheric field concentrations suggesting that they trace magnetic field lines. These images have been historically used as proxies…

X-ray spectra from stellar coronae are reprocessed by the underlying photosphere through scattering and photoionization events. While reprocessed X-ray spectra reaching a distant observer are at a flux level of only a few percent of that of…

Using new and archival spectra from the Goddard High Resolution Spectrograph, we have searched for evidence of chromospheric and transition region emission in six stars of mid- to late-A spectral type. Two of the stars, alpha Aql (A7 IV-V)…

We observed small scale magnetic flux emergence in a sunspot moat region by the Solar Optical Telescope (SOT) aboard the Hinode satellite. We analyzed filtergram images observed in the wavelengths of Fe 6302 angstrom, G-band and Ca II H. In…

We simulate decaying turbulence in a homogeneous pair plasma using three dimensional electromagnetic particle-in-cell (PIC) method. A uniform background magnetic field permeates the plasma such that the magnetic pressure is three times…

Between 2017 and 2024, the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory has observed numerous white-light solar flares (WLFs). HMI spectro-polarimetric observations of certain WLFs, in particular the X9.3…

Imaging observations of the solar lower atmosphere by the Atmosphere Imaging Assembly (AIA) have been mostly used as the context, and their quantitative information has been much less explored. The chromosphere responds rapidly to energy…

Solar observations in the mid-infrared 8-14 \mu\m band continuum were carried out with cadence of 5 frames per second, in December 2007. Rapid small heated sources, with typical duration of the order of seconds, were found on the bright…

Here we present the study of a compact emission source during an X1.3 flare on 2022-March-30. Within a $\sim41$~s period (17:34:48 UT to 17:35:29 UT), IRIS observations show spectral lines of Mg II, C II and Si IV with extremely broadened,…