相关论文: Ellerman bombs at high resolution III. Simultaneou…

Our understanding of the process of fast reconnection has undergone a dramatic change in the last 10 years driven, in part, by the availability of high-resolution numerical simulations that have consistently demonstrated the break-up of…

Distant luminous Lyman-alpha emitters are excellent targets for detailed observations of galaxies in the epoch of reionisation. Spatially resolved observations of these galaxies allow us to simultaneously probe the emission from young…

On the Sun,jets in light bridges are frequently observed with high-resolution instruments.The respective roles played by convection and the magnetic field in triggering such jets are not yet clear.We report a small fan-shaped jet along a LB…

The emission spectrum has been calculated of a homogeneous pure hydrogen layer, which parameters are typical for a flare on a red dwarf. The ionization and excitation states were determined by the solution of steady-state equations taking…

We present high-resolution, phase-resolved spectroscopic observations of the polar EF Eri, obtained with SALT and the SAAO 1.9-m telescope during its recent emergence from a three-decade-long low state. The average spectrum shows strong…

Burst-like events with signatures in the UV are often observed co-spatial to strong line-of-sight photospheric magnetic fields. Several authors, for example, have noted the spatial relationship between Ellerman bombs (EBs) and Moving…

We study the formation of a partially ionized zone behind the usual H II zone in photo-ionized gas for gas density intermediate between ordinary H II regions and AGN BLRs and without X-rays. While Lyman continuum photons are depleted before…

Magnetic reconnection modulated by non-local disturbances in the solar atmosphere has been investigated theoretically, but rarely observed. In this study, employing Ha and extreme ultraviolet (EUV) images and line of sight magnetograms, we…

The emission-lines in the active galaxy IRAS\,0421+0400 show a dramatic ($\sim$\,900\kms) increase in the velocity spread at the position of radio hot-spots which are located at the beginning of extended radio lobes. We study a simple…

Blazars exhibit flares across the electromagnetic spectrum. Many $\gamma$-ray flares are highly correlated with flares detected at optical wavelengths; however, a small subset appears to occur in isolation, with little or no variability…

Particle acceleration is one of the most significant features that are ubiquitous among space and cosmic plasmas. It is most prominent during flares in the case of the Sun, with which huge amount of electromagnetic radiation and high-energy…

We report a detailed analysis of a failed eruption and flare in active region 12018 on 2014 April 3 using multiwavelength observations from SDO/AIA, IRIS, STEREO, and Hinode/SOT. At least four jets were observed to emanate from the cusp of…

We use 2.5-D electromagnetic particle-in-cell simulation code to investigate the acceleration of electrons in solar coronal holes through the interaction of Alfv\'en waves with an interplume region. The interplume is modeled by a cavity…

We are leading a comprehensive multi-waveband monitoring program of 34 gamma-ray bright blazars designed to locate the emission regions of blazars from radio to gamma-ray frequencies. The "maps" are anchored by sequences of images in both…

We show fifty-seven enhanced radiation level events taken from new measurements on commercial altitude (greater than 9 km) aircraft that are analogous to planes flying through radiation clouds. More accurately, the plane is likely to be…

Quiescent filaments appear as absorption features on the solar disk when observed in chromospheric lines and at continuum wavelengths in the millimeter (mm) range. Active region (AR) filaments are their small-scale, low-altitude analogues,…

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…

We present VLT/SINFONI near-infrared (NIR) integral field spectroscopy of six $z \sim 0.2$ Lyman break galaxy "analogs" (LBAs), from which we detect HI, HeI, and [FeII] recombination lines, and multiple H$_2$ ro-vibrational lines in…

Sudden jets of collimated plasma arise from many locations on the Sun, including active regions. The magnetic field along which a jet emerges is often open to interplanetary space, offering a clear "escape route" for any flare-accelerated…

Very precise satellite photometry has revealed a large number of variable stars whose variability is caused either by surface spots or by binarity. Detailed studies of such variables provide insights into the physics of these objects. We…