Related papers: Temporal evolution of mottles observed in H_alpha
In this paper, we analyze the physical properties of dark mottles in the chromospheric network using two dimensional spectroscopic observations in H-alpha obtained with the Gottingen Fabry-Perot Spectrometer in the Vacuum Tower Telescope at…
We present high spatial and high temporal resolution observations of the quiet Sun in H-alpha obtained with the Swedish 1-m Solar Telescope on La Palma. We observe that many mottles, jet-like features in the quiet Sun, display clear up- and…
A number of recent investigations have revealed that transverse waves are ubiquitous in the solar chromosphere. The vast majority of these have been reported in limb spicules and active region fibrils. We investigate long-lived, quiet Sun,…
In the present work, we study the periodicities of oscillations in dark fine structures using observations of a network and a semi-active region close to the solar disk center. We simultaneously obtained spatially high resolution time…
We study the structure and evolution of the magnetic field of the quiet Sun by investigating weak spectro-polarimetric signals. To this end, we observed a quiet region close to the disk center with the German VTT in Tenerife, July 07, 2006.…
We present chromospheric cloud modeling on the basis of H-alpha profile-sampling images taken with the Interferometric Bidimensional Spectrometer (IBIS) at the Dunn Solar Telescope (DST). We choose the required reference background profile…
We present unprecedented high resolution H-alpha observations, obtained with the Swedish 1-m Solar Telescope, that, for the first time, spatially and temporally resolve dynamic fibrils in active regions on the Sun. These jet-like features…
A 50 min time series of one-dimensional slit-spectrograms, taken in quiet sun at disk center, observed at the German Vacuum Tower Telescope (Observatorio del Teide), was used to study the global and spatial variations of different line…
We present observations of a solar quiet region obtained by the ground-based Dutch Open Telescope (DOT), and by instruments on the spacecraft SOHO and TRACE. The observations were obtained during a coordinated observing campaign on October…
A continuous set of echelle spectra of TW Hya, taken with the MIKE spectrograph on the Magellan2/Clay telescope at Las Campanas Observatory in April 2006 reveals systematic variations in the flux, velocity, and profile of the H-alpha…
The Hanle effect in strong spectral lines is the physical mechanism that should be increasingly exploited for quantitative explorations of the magnetism of the quiet solar chromospheric plasma. Here we show, by means of multilevel radiative…
A particularly interesting line for exploring the physical conditions of the quiet solar chromosphere is H$\alpha$, but its intensity profile is magnetically insensitive and the small circular polarization signatures produced by the…
DOT high-resolution imagery suggests that only internetwork-spanning H-alpha "mottles" constitute the quiet-sun chromosphere, whereas more upright network "straws" in "hedge rows" reflect transition-region conditions.
High-frequency waves (5 mHz to 20mHz) have previously been suggested as a source of energy accounting partial heating of the quiet solar atmosphere. The dynamics of previously detected high-frequency waves is analysed here. Image sequences…
The convectively driven, weakly magnetized regions of the solar photosphere dominate the Sun's surface at any given time, but the temporal variations of these quiet regions of the photosphere throughout the solar cycle are still not well…
The solar chromosphere observed in H-alpha consists mostly of narrow fibrils. The longest typically originate in network or plage and arch far over adjacent internetwork. We use data from multiple telescopes to analyze one well-observed…
The energy spectra of galactic cosmic rays carry fundamental information regarding their origin and propagation. These spectra, when measured near Earth, are significantly affected by the solar magnetic field. A comprehensive description of…
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…
The solar photosphere is filled by a magnetic field which is tangled on scales much smaller than the resolution capability of solar telescopes. This hidden magnetic field can be investigated via the Hanle effect. In 2007 we started a…
We study the evolution of a mini-filament eruption in a quiet region at the center of the solar disk and its impact on the ambient atmosphere. We used high-spectral resolution imaging spectroscopy in H$\alpha$ acquired by the echelle…