Related papers: EUV Analysis of a Quasi-Static Coronal Loop Struct…
It is generally accepted that densities of quiet sun and active region plasma are sufficiently low to justify the optically thin approximation, and it is commonly used in the analysis of line emissions from plasma in the solar corona.…
Kink oscillations, which are frequently observed in coronal loops and prominences, are often accompanied by extreme-ultraviolet (EUV) waves. However, much more needs to be explored regarding the causal relationships between kink…
We report decaying quasi-periodic intensity oscillations in the X-ray (6-12 keV) and extreme ultraviolet (EUV) channels (131, 94, 1600, 304 \AA) observed by the Fermi GBM (Gamma-ray Burst Monitor) and SDO/AIA, respectively, during a C-class…
The "middle corona" is a critical transition between the highly disparate physical regimes of the lower and outer solar corona. Nonetheless, it remains poorly understood due to the difficulty of observing this faint region (1.5-3 solar…
Many models for coronal loops have difficulty explaining the observed EUV brightness of the transition region, which is often significantly less than theoretical models predict. This discrepancy has been addressed by a variety of approaches…
Longitudinal intensity oscillations along coronal loops that are interpreted as signatures of magneto-acoustic waves are observed frequently in different coronal structures. The aim of this paper is to estimate the physical parameters of…
We present a detailed X-ray analysis and imaging of stellar coronae of five coronally connected eclipsing binaries, namely, 44 Boo, DV Psc, ER Vul, XY UMa, and TX Cnc. Both components of these binaries are found to be active. The X-ray…
Magnetic energy is required to heat the corona, the outer atmosphere of the Sun, to millions of degrees. We study the nature of the magnetic energy source that is probably responsible for the brightening of coronal loops driven by…
We present a study of the temporal evolution of coronal loops in active regions and its implications for the dynamics in coronal loops. We analyzed images of the Atmospheric Imaging Assembly (AIA) on the Solar Dynamics Observatory (SDO) at…
The nanoflare model of coronal heating is one of the most successful scenarios to explain, within a single framework, the diverse set of coronal observations available with the present instrument resolutions. The model is based on the idea…
One scenario proposed to explain the million degrees solar corona is a finely-stranded corona where each strand is heated by a rapid pulse. However, such fine structure has neither been resolved through direct imaging observations nor…
We used data from the Helioseismic and Magnetic Imager (HMI), and Atmospheric Imaging Assembly (AIA) on the \textit{Solar Dynamics Observatory} (SDO) to study coronal loops at small scales, emerging in the quiet Sun. With HMI line-of-sight…
We have explored the magnetic flux evolution and temperature variation in a coronal-hole region, using Big Bear Solar Observatory (BBSO) deep magnetograms and {\it SOHO}/EIT images observed from 2005 October 10 to 14. For comparison, we…
We study the formation of transient loops in the core of the AR 11890. For this purpose, we have used the observations recorded by the Atmospheric Imaging Assembly (AIA) and the Interface Region Imaging Spectrograph (IRIS). For photospheric…
One of the proposed damping mechanisms of coronal (transverse) loop oscillations in the kink-mode is resonant absorption as a result of the Alfven speed variation at the outer boundary of coronal loops. Analytical expressions for the period…
One puzzling observed property of coronal loops is that they are of roughly constant thickness along their length. Various studies have found no consistent pattern of width variation along the length of loops observed by TRACE and SOHO.…
For the first time, we present and discuss EUV radiances of the solar transition region (TR) and corona obtained during a solar cycle. The measurements were obtained with the SOHO/coronal diagnostic spectrometer (CDS) during the period from…
IRIS data allow us to study the solar transition region (TR) with an unprecedented spatial resolution of 0.33 arcsec. On 2013 August 30, we observed bursts of high Doppler shifts suggesting strong supersonic downflows of up to 200 km/s and…
Observations of the off-limb corona with the SWAP wide-field telescope in the 174\,\AA\ passband onboard the PROBA2 mission provide an opportunity to study post-eruptive processes in the dimming regions. We investigate morphology, temporal…
The heating of coronal loops is investigated to understand the observational consequences in terms of the thermodynamics and radiative losses from the Sun as well as the magnetized coronae of stars with an outer convective envelope. The…