Related papers: Solar ALMA predictions: tutorial
Solar flares are driven by the release of magnetic energy from reconnection events in the solar corona, whereafter energy is transported to the chromosphere, heating the plasma and causing the characteristic radiative losses. In the…
We show that the coronal heating and the acceleration of the fast solar wind in the coronal holes are natural consequence of the footpoint fluctuations of the magnetic fields at the photosphere by one-dimensional, time-dependent, and…
The precise mechanisms that provide the non-radiative energy for heating the chromosphere and the corona of the Sun and other stars are at the focus of intense contemporary research. Observations at submm/mm wavelengths are particularly…
The Atacama Large Millimeter/submillimeter Array (ALMA) offers new diagnostic possibilities that complement other commonly used diagnostics for the study of our Sun. In particular, ALMA's ability to serve as an essentially linear…
We have extended our previous observation (Lim et al. 2008) of NGC1275 covering a central radius of ~10kpc to the entire main body of cool molecular gas spanning ~14kpc east and west of center. We find no new features beyond the region…
Oscillations of coronal loops in the Sun have been reported in both imaging and spectral observations at the onset of flares. Images reveal transverse oscillations, whereas spectra detect line-of-sight velocity or Doppler-shift…
We consider the oblique fragmentation of the current layer as a result of the thermal instability described in Ledentsov (Sol. Phys. 296, 74, 2021a). It is shown that the fragmentation transverse to the current is a natural feature of the…
ALMA observations of protoplanetary disks in dust continuum emission reveal a variety of annular structures. Attributing the existence of such features to embedded planets is a popular scenario, supported by studies using hydrodynamical…
We have performed 5 night spectroscopic observation of the Halpha line of EV Lac with a medium wavelength resolution (R~ 10,000) using the 2m Nayuta telescope at the Nishi-Harima Astronomical Observatory. EV Lac always possesses the Halpha…
We consider MHD waves as a heating source of cool cores of galaxy clusters. In particular, we focus on transverse waves (Alfven waves), because they can propagate a longer distance than longitudinal waves (sound waves). Using MHD…
Plasma with a temperature close to the chromospheric one is ejected in solar eruptions. Such plasma can occult some part of emission of compact sources in active regions as well as quiet solar areas. Absorption phenomena can be observed in…
Recent data support the idea that the filaments observed in H_alpha emission near the centres of some galaxy clusters were shaped by bulk flows within their intracluster media. We present numerical simulations of evaporated clump material…
Results of multi-frequency VLBA polarization imaging for sources showing evidence of quasi-periodic variations in their total flux density are discussed. Possible origins of the observed behavior are proposed.
Simultaneous measurements of the intensity and phase of a probe wave reflected from an interface between silica and elemental alpha-gallium reveal its very strong optical nonlinearity, affecting both these parameters of the reflected wave.…
Solar observations at sub-mm, mm and cm wavelengths offer a straightforward diagnostic of physical conditions in the solar atmosphere because they yield measurement of brightness temperature which, for optically thick features, equals…
We study the formation and evolution of a turbulent spectrum of Alfv\'en waves driven by reflection off the solar wind density gradients, starting from the coronal base up to 17 solar radii, well beyond the Alfv\'enic critical point. The…
The Atacama Large Millimeter/sub-millimeter Array (ALMA) has provided us with an excellent diagnostic tool for studies of the dynamics of the Solar chromosphere, albeit through a single receiver band at one time presently. Each ALMA band…
Far ultraviolet emission has been detected from a knot of Halpha emission in the Horseshoe filament, far out in the NGC 1275 nebula. The flux detected relative to the brightness of the Halpha line in the same spatial region is very close to…
The outflows of oxygen-rich asymptotic giant branch (AGB) stars are thought to be driven by radiation pressure by photon scattering on grains with sizes of tenths of microns. The details of the formation of dust in the extended atmospheres…
We have modeled the time-variable profiles of the Halpha emission line from the non-axisymmetric disk and debris tail created in the tidal disruption of a solar-type star by a million solar mass black hole. We find that the line profiles at…