Related papers: The Chromospheric Telescope
The Chromospheric Telescope (ChroTel) is a small 10-cm robotic telescope at Observatorio del Teide on Tenerife (Spain), which observes the entire Sun in H$\alpha$, CaII K, and HeI 10830\AA. We present a new calibration method that includes…
Polar crown filaments form above the polarity inversion line between the old magnetic flux of the previous cycle and the new magnetic flux of the current cycle. Studying their appearance and their properties can lead to a better…
The solar chromosphere has historically been studied from spectral lines in the visible and UV, notably H{\alpha}, Ca ii, Mg ii and Ly{\alpha}. Observations at long UV wavelengths (304, 1600 and 1700 {\AA}) from space have been recently…
We describe the first instrument of a Cosmic Microwave Background experiment for mapping cosmological structures on medium angular scales (the COSMOSOMAS experiment) and diffuse Galactic emission. The instrument is located at Teide…
We report the observations of the solar chromosphere from a newly commissioned solar telescope at the incursion site near Pangong Tso lake in Merak (Leh/Ladakh). This new H$_{\alpha}$ telescope at the Merak site is identical to the…
The chromosphere is a highly complex and dynamic layer of the Sun, that serves as a conduit for mass and energy supply between two, very distinct regions of the solar atmosphere, namely, the photosphere and corona. Inferring magnetic fields…
Observations of chromospheric spectral lines near and beyond the solar limb provide information on the solar chromosphere without any photospheric contamination. For ground-based observations near and off the limb with real-time image…
In this work we use solar observations with the ALMA radio telescope at the wavelength of 1.21 mm. The aim of the analysis is to improve understanding of the solar chromosphere, a dynamic layer in the solar atmosphere between the…
We present observations of the solar chromosphere obtained simultaneously with the Atacama Large Millimeter/submillimeter Array (ALMA) and the Interface Region Imaging Spectrograph (IRIS). The observatories targeted a chromospheric plage…
The center-to-limb variations (CLVs) of photospheric and chromospheric spectral lines were obtained in 2025 July and August using drift scans from the echelle spectrograph of the 0.7 m Vacuum Tower Telescope at the Observatorio del Teide…
The solar chromosphere is a vigorously dynamic region of the sun, where waves and magnetic fields play an important role. To improve chromospheric diagnostics, we present new observations in Ca II 8542 carried out with the SST/CRISP on La…
Observations of circumstellar environments to look for the direct signal of exoplanets and the scattered light from disks has significant instrumental implications. In the past 15 years, major developments in adaptive optics, coronagraphy,…
We present in this reference paper an instrumental project dedicated to the monitoring of solar activity during solar cycle 25. It concerns the survey of fast evolving chromospheric events implied in Space Weather, such as flares, coronal…
This paper reports on the installation and observations of a new solar telescope installed on 7th October, 2014 at the Kodaikanal Observatory. The telescope is a refractive type equipped with a tunable Lyot H$_{\alpha}$ filter. A CCD camera…
The primary challenge of GOLF-NG (Global Oscillations at Low Frequency New Generation) is the detection of the low-frequency solar gravity and acoustic modes, as well as the possibility to measure the high-frequency chromospheric modes. On…
TolTEC is a new camera being built for the 50-meter Large Millimeter-wave Telescope (LMT) in Puebla, Mexico to survey distant galaxies and star-forming regions in the Milky Way. The optical design simultaneously couples the field of view…
In this contribution we present preliminary results of a study applied to the Observatories of Roque de Los Muchachos (La Palma) and Teide (Tenerife) in Canary Islands aiming to investigate the possibility to implement an automatic system…
We present here a new robotic telescope called TRAPPIST (TRAnsiting Planets and PlanetesImals Small Telescope). Equipped with a high-quality CCD camera mounted on a 0.6 meter light weight optical tube, TRAPPIST has been installed in April…
High-resolution spectra of a giant solar quiescent filament were taken with the Echelle spectrograph at the Vacuum Tower Telescope (VTT; Tenerife, Spain). A mosaic of various spectroheliograms (H\alpha, H\alpha\ +/- 0.5\AA\ and Na D2) were…
Chromospheric magnetic fields are of paramount importance in understanding the dynamics of energetic events in the solar atmosphere. At the Kodaikanal Solar Observatory, several polarimeters were developed in the past to study the active…