Abstract The Interface Region Imaging Spectrograph (IRIS) has been obtaining near-and far-
ultraviolet images and spectra of the solar atmosphere since July 2013. IRIS is the highest …

The detection of Earth-like planets with the radial-velocity (RV) method is currently limited by
the presence of stellar activity signatures. On rotational time-scales, spots and plages (or …

The inference of the underlying state of the plasma in the solar chromosphere remains
extremely challenging because of the nonlocal character of the observed radiation and …

The Atacama Large Millimeter/submillimeter Array (ALMA) offers new diagnostic possibilities
that complement other commonly used diagnostics for the study of the Sun. In particular …

Context. The solar chromosphere is heated to temperatures higher than predicted by
radiative equilibrium. This excess heating is greater in active regions where the magnetic …

Understanding the complex dynamics and structure of the upper solar atmosphere strongly
benefits from the use of a combination of several diagnostics. Frequently, such diverse …

Context. Numerical simulations of the solar chromosphere predict a diverse thermal
structure with both hot and cool regions. Observations of plage regions in particular typically …

Routine ultraviolet imaging of the Sun's upper atmosphere shows the spectacular
manifestation of solar activity; yet, we remain blind to its main driver, the magnetic field …

The study of the preflare environment is of great importance to understanding what drives
solar flares. k-means clustering, an unsupervised machine-learning technique, has the …

Context. Chromospheric fibrils are thin and elongated structures that connect nearby
photospheric magnetic field concentrations of opposite polarities. Aims. We assess the …