Search Publications
The European Solar Telescope
Heinzel, P.; Strassmeier, K. G.; Schmidt, W. +278 more
The European Solar Telescope (EST) is a project aimed at studying the magnetic connectivity of the solar atmosphere, from the deep photosphere to the upper chromosphere. Its design combines the knowledge and expertise gathered by the European solar physics community during the construction and operation of state-of-the-art solar telescopes operati…
Coronal condensation as the source of transition-region supersonic downflows above a sunspot
Tian, Hui; Peter, Hardi; Hou, Zhenyong +3 more
Context. Plasma loops or plumes rooted in sunspot umbrae often harbor downflows with speeds of 100 km s−1. These downflows are supersonic at transition region temperatures of ∼0.1 MK. The source of these flows is not well understood.
Aims: We aim to investigate the source of sunspot supersonic downflows (SSDs) in active region 1274…
The Solar ALMA Science Archive (SALSA). First release, SALAT, and FITS header standard
Mohan, Atul; Wedemeyer, Sven; Jafarzadeh, Shahin +5 more
In December 2016, the Atacama Large Millimeter/submillimeter Array (ALMA) carried out the first regular observations of the Sun. These early observations and the reduction of the respective data posed a challenge due to the novelty and complexity of observing the Sun with ALMA. The difficulties with producing science-ready, time-resolved imaging p…
Eruptions from coronal bright points: A spectroscopic view by IRIS of a mini-filament eruption, QSL reconnection, and reconnection-driven outflows
Madjarska, Maria S.; Wiegelmann, Thomas; Mackay, Duncan H. +2 more
Context. Our study investigates a mini-filament eruption associated with cancelling magnetic fluxes. The eruption originates from a small-scale loop complex commonly known as a coronal bright point (CBP). The event is uniquely recorded in both the imaging and spectroscopic data taken with the Interface Region Imaging Spectrograph (IRIS).
Aims…
Occurrence and statistics of IRIS bursts
Kleint, Lucia; Panos, Brandon
Small reconnection events in the lower solar atmosphere can lead to its heating, but whether such heating can propagate into higher atmospheric layers and potentially contribute to coronal heating is an open question. We carry out a large statistical analysis of all IRIS observations from 2013 and 2014. We identified "IRIS burst" (IB) spectra usin…
Plausibility of ultraviolet burst generation in the low solar chromosphere
Cheng, Guanchong; Ni, Lei; Lin, Jun
Context. Ultraviolet (UV) bursts and Ellerman bombs (EBs) are small-scale magnetic reconnection events taking place in the highly stratified, low solar atmosphere. The plasma density, reconnection mechanisms, radiative cooling and transfer processes clearly differ from one layer of the atmosphere to the next. In particular, EBs are believed to for…
Chromospheric emission from nanoflare heating in RADYN simulations
De Pontieu, B.; Rouppe van der Voort, L.; Carlsson, M. +4 more
Context. Heating signatures from small-scale magnetic reconnection events in the solar atmosphere have proven to be difficult to detect through observations. Numerical models that reproduce flaring conditions are essential in understanding how nanoflares may act as a heating mechanism of the corona.
Aims: We study the effects of non-thermal e…
Power distribution of oscillations in the atmosphere of a plage region. Joint observations with ALMA, IRIS, and SDO
Wedemeyer, Sven; Fleck, Bernhard; Jafarzadeh, Shahin +3 more
Context. Joint observations of the Atacama Large Millimeter/Submillimeter Array (ALMA) with other solar observatories can provide a wealth of opportunities for understanding the coupling between different layers of the solar atmosphere.
Aims: We present a statistical analysis of the power distribution of oscillations in a plage region in acti…
Spectroscopic observation of a transition region network jet
Peter, H.; Chitta, L. P.; Gorman, J.
Aims: Ubiquitous transition region (TR) network jets are considered to be substantial sources of mass and energy to the corona and solar wind. We conduct a case study of a network jet to better understand the nature of mass flows along its length and the energetics involved in its launch.
Methods: We present an observation of a jet with …
Radiative losses in the chromosphere during a C-class flare
Leenaarts, J.; de la Cruz Rodríguez, J.; Díaz Baso, C. J. +2 more
Context. Solar flares release an enormous amount of energy (∼1032 erg) into the corona. A substantial fraction of this energy is transported to the lower atmosphere, which results in chromospheric heating. The mechanisms that transport energy to the lower solar atmosphere during a flare are still not fully understood.
Aims: We aim …