Related papers: Chromospheric peculiar off-limb dynamical events f…
We study broad red-shifted emission in chromospheric and transition region lines that appears to correspond to a form of post-flare coronal rain. Profiles of Mg II, C II and Si IV lines were obtained using the IRIS instrument before, during…
Spicules are ubiquitous, small-scale features in the solar atmosphere, exhibiting a jet-like appearance most clearly identified by their apparent motion in off-limb observations. While they are often interpreted as narrow, thread-like…
Loops are one of the fundamental structures that trace the geometry of the magnetic field in the solar atmosphere. Their evolution and dynamics provide a crucial proxy for studying how the magnetized structures are formed and heated in the…
We characterize, for the first time, type-II spicules in Ca II K 3934\AA\ using the CHROMIS instrument at the Swedish 1-m Solar Telescope. We find that their line formation is dominated by opacity shifts with the K$_{3}$ minimum best…
We focus on detecting and studying quasi-periodic propagating features that have been interpreted both in terms of slow magneto-acoustic waves and of high speed upflows. We analyze long duration spectroscopic observations of the on-disk…
We investigate off-limb active region and quiet Sun corona using spectroscopic data. Active region is clearly visible in several spectral lines formed in the temperature range of 1.1--2.8 MK. We derive electron number density using line…
Hydrodynamic jets are unstable to the kink instability (m=1 mode in cylindrical geometry) owing to the centripetal force, which increases the transverse displacement of the jet. When the jet moves along a magnetic field, then the Lorentz…
Observations of chromospheric spectral lines near and beyond the solar limb provide information on the solar chromosphere without any photospheric contamination. For ground-based observations near and off the limb with real-time image…
We analyze flare-associated transverse oscillations in a quiescent solar prominence on 8-9 September, 2010. Both the flaring active region and the prominence were located near the West limb, with a favorable configuration and viewing angle.…
Fibrillar structures are ubiquitous in the solar chromosphere and their potential for mediating the mass and energy transport in the solar atmosphere is undeniable. An accurate determination of their properties requires the use of advanced…
High resolution spectral observations of the lower solar atmosphere (chromosphere and transition region) during coronal heating events, in combination with predictions from models of impulsively heated loops, provide powerful diagnostics of…
In this paper, we analyze the high-resolution UV spectra for a C1.7 solar flare (SOL2017-09-09T06:51) observed by the \textit{Interface Region Imaging Spectrograph} (\textit{IRIS}). {We focus on the spectroscopic observations at the…
We present observations of the solar chromosphere obtained simultaneously with the Atacama Large Millimeter/submillimeter Array (ALMA) and the Interface Region Imaging Spectrograph (IRIS). The observatories targeted a chromospheric plage…
We report on the spectral features of the Si IV 1402.77 \AA, C II 1334.53 \AA, and Mg II h or k lines, formed in the layers from the transition region to the chromosphere, in three two-ribbon flares (with X-, M-, and C-class) observed with…
Observations from the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO) reveal ubiquitous episodic outflows (jets) with an average speed around 120 km s-1 at temperatures often exceeding a million degree in…
We study the properties of waves in a facular region of moderate strength in the photosphere and chromosphere. Our aim is to analyse statistically the wave periods, power and phase relations as a function of the magnetic field strength and…
The physical processes causing energy exchange between the Sun's hot corona and its cool lower atmosphere remain poorly understood. The chromosphere and transition region (TR) form an interface region between the surface and the corona that…
During solar flares, a considerable portion of the flare atmosphere becomes heated; however, the energy deposition process is still unclear, especially in the lower solar atmosphere. Here, we present spectroscopic and imaging observations…
Solar radio spikes are short duration and narrow bandwidth fine structures in dynamic spectra observed from GHz to tens of MHz range. Their very short duration and narrow frequency bandwidth are indicative of sub-second small-scale energy…
Solar jets are impulsive, collimated plasma ejections that are triggered by magnetic reconnection. They are observed for many decades in various temperatures and wavelengths, therefore their kinematic characteristics, such as velocity and…