Related papers: Atmosphere above a large solar pore
Recent high resolution spectropolarimetric observations from Hinode detected the presence of supersonic downflows in a sunspot light bridge (Louis et al. 2009). These downflows occurred in localized patches, close to regions where the field…
We investigated the radiative emission of different types of solar features in the spectral range of the Ca II K line. We analyzed full-disk 2k x 2k observations from the PSPT Precision Solar Photometric Telescope. The data were obtained by…
Sunspot chromospheres display vigorous oscillatory signature when observed in chromospheric diagnostics like the strong Ca II lines and H-alpha. New high-resolution sunspot observations from the Swedish 1-m Solar Telescope show the…
We analyze the high-resolution observations from the 1.6m telescope at Big Bear Solar Observatory that cover an active region filament. Counter-streaming motions are clearly observed in the filament. The northern end of the…
High resolution spectropolarimetric observations of 3 sunspots taken with Hinode demonstrate the existence of supersonic downflows at or close to the umbra-penumbra boundary which have not been reported before. These downflows are confined…
With the high tempo-spatial \emph{Interface Region Imaging Spectrograph} 1330 {\AA} images, we find that many bright structures are rooted in the light bridge of NOAA 12192, forming a \emph{light wall}. The light wall is brighter than the…
Context. A large prominence was observed on September 24, 2013, for three hours (12:12 UT -15:12 UT) with the newly launched (June 2013) Interface Region Imaging Spectrograph (IRIS), THEMIS (Tenerife), the Hinode Solar Optical Telescope…
We analyze a 1-hour time series of Ca II H intensity spectra and polarimetric spectra around 630 nm to derive the signature of the chromospheric heating and to investigate its relation to magnetic fields. We derived several characteristic…
Context. The radiative losses in the solar chromosphere vary from 4~kW~m$^{-2}$ in the quiet Sun, to 20~kW~m$^{-2}$ in active regions. The mechanisms that transport non-thermal energy to and deposit it in the chromosphere are still not…
Active prominences exhibit plasma motions, resulting in difficulties with the interpretation of spectroscopic observations. These solar features being strongly influenced by the radiation coming from the solar disk, Doppler dimming or…
The acoustic resonator is an important model for explaining the three-minute oscillations in the chromosphere above sunspot umbrae. The steep temperature gradients at the photosphere and transition region provide the cavity for the acoustic…
The goal is to compare the intricate details of the magnetic and flow fields around two solar pores, where one is part of an active region and the other is an isolated pore, with a secondary goal of demonstrating the scientific capabilities…
We present new high-resolution spectro-polarimetric Ca II 8542 observations of umbral flashes in sunspots. At nearly 0.18", and spanning about one hour of continuous observation, this is the most detailed dataset published thus far. Our…
We report the discovery of supersonic downflows in a sunspot light bridge using measurements taken with the spectropolarimeter on board the Hinode satellite. The downflows occur in small patches close to regions where the vector magnetic…
We present here a continuation of our ongoing project of multiwavelength optical observations aimed at studying the chromosphere of active binary systems using the information provided for several optical spectroscopic features that are…
New high-resolution high signal-to-noise spectra of the $z=1.15$ damped Lyman $\alpha$ (DLA) system toward the quasi-stellar object HE 0515-4414 reveal absorption lines of the multiplets 2 and 3 in \ion{C}{i}. The resonance lines are seen…
Oscillations in sunspot umbrae exhibit remarkable differences between the photosphere and chromosphere. We evaluate two competing scenarios proposed for explaining those observations: a chromospheric resonant cavity and waves traveling from…
The Ca II infrared triplet is one of the few magnetically sensitive chromospheric lines available for ground-based observations. We present spectropolarimetric observations of the 8498 A and 8542 A lines in a quiet Sun region near a…
Recent progress in instrumentation enables solar observations with high resolution simultaneously in the spatial, temporal, and spectral domains. We use such high-resolution observations to study small-scale structures and dynamics in the…
NASA's Interface Region Imaging Spectrograph (IRIS) small explorer mission will study how the solar atmosphere is energized. IRIS contains an imaging spectrograph that covers the Mg II h&k lines as well as a slit-jaw imager centered at Mg…