Related papers: Optimal spectral lines for measuring chromospheric…
For many years various asymmetrical profiles of different spectral lines emitted from solar flares have been frequently observed. These asymmetries or line shifts are caused predominantly by vertical mass motions in flaring layers and they…
Auroral emission lines result from the interaction between magnetic field and stellar wind, offering valuable insights into physical properties and processes occurring within magnetospheres of celestial bodies. While extensively studied in…
Since the discovery by Hale in the early 1900s that sunspots harbor strong magnetic field, magnetism has become increasingly important in our understanding of processes on the Sun and in the Heliosphere. Many current and planned instruments…
The design and later use of modern spectropolarimeters and magnetographs require a number of tolerance specifications that allow the developers to build the instrument and then the scientists to interpret the data accuracy. Such…
Full disk vector magnetic fields are used widely for developing better understanding of large-scale structure, morphology, and patterns of the solar magnetic field. The data are also important for modeling various solar phenomena. However,…
The Mg ii h&k lines are key diagnostics of the solar chromosphere. They are sensitive to the temperature, density, and non-thermal velocities in the chromosphere. The average Mg ii h&k line profiles arising from previous 3D chromospheric…
Here we report on the first observational investigation of the Zeeman effect in the G band around 4305 A. Our spectropolarimetric observations of sunspots with the Zurich Imaging Polarimeter at the IRSOL facility confirm our previous…
The distribution of magnetic field strength at different levels in the solar photosphere outside active regions was obtained on the basis of the 2D MHD simulation of magnetogranulation and the synthesis of the V profiles of the Fe I 1564.8…
Plages are small concentrations of strong, nearly vertical magnetic fields in the solar photosphere that expand with height. A high spatial and spectral resolution that can resolve their fine structure is required to characterize them, and…
Solar observations with the Atacama Large Millimeter/submillimeter Array (ALMA) provide us with direct measurements of the brightness temperature in the solar chromosphere. We study the temperature distributions obtained with ALMA Band 6…
Direct solar coronal magnetic field measurements have become possible since recent development of high-sensitivity infrared detection technology. The SOLARC instrument installed on Mt. Haleakala is such a polarimetric coronagraph that was…
Context. Recent high angular resolution polarimetric continuum observations of circumstellar disks provide new insights into their magnetic field. However, direct constraints are limited to the plane of sky component of the magnetic field.…
We present novel spectropolarimetric observations of the hydrogen H$\alpha$ line taken with the Z\"urich Imaging Polarimeter (ZIMPOL) at the Gregory Coud\'e Telescope of the Istituto Ricerche Solari Locarno (IRSOL). The linear polarization…
Solar UV emission has a profound impact on the upper terrestrial atmosphere. Because of instrumental constraints, however, solar proxies often need to be used as substitutes for the solar spectral variability. Finding proxies that properly…
The chromosphere above active regions (ARs) on the Sun hosts magnetized supersonic downflows. Studies of these supersonic downflows help to decipher the magnetic fine structure and dynamics of the chromosphere. We perform a statistical…
Arch filament systems occur in active sunspot groups, where a fibril structure connects areas of opposite magnetic polarity, in contrast to active region filaments that follow the polarity inversion line. We used the GREGOR Infrared…
We present the magnetic landscape of the polar region of the Sun that is unprecedented in terms of high spatial resolution, large field of view, and polarimetric precision. These observations were carried out with the Solar Optical…
We present accurate measurements of the central wavelengths of 4947 atomic absorption lines in the solar optical spectrum. The wavelengths, precise to a level ~ 50-150 m/s, are given for both flux and disc-centre spectra, as measured in…
The linear polarization produced by scattering processes in the hydrogen Lyman alpha line of the solar disk radiation is a key observable for probing the chromosphere-corona transition region (TR) and the underlying chromospheric plasma.…
Details of the magnetic field in the quiet Sun chromosphere are key to our understanding of essential aspects of the solar atmosphere. We aim to determine the longitudinal magnetic field component (B_lon) of quiet Sun regions depending on…