196 citations · 1.8k across the 25 of their papers we have counts for
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Heating of the solar chromosphere through current dissipation
J. M. da Silva Santos, S. Danilovic, J. Leenaarts +5
The solar chromosphere is heated to temperatures higher than predicted by radiative equilibrium. This excess heating is greater in active regions where the magnetic field is strong…
Active region chromospheric magnetic fields
G. J. M. Vissers, S. Danilovic, X. Zhu +5
Context. A proper estimate of the chromospheric magnetic fields is believed to improve modelling of both active region and coronal mass ejection evolution. Aims. We investigate the…
Non-LTE inversions of a confined X2.2 flare: I. Vector magnetic field in the photosphere and chromosphere
G. J. M. Vissers, S. Danilovic, J. de la Cruz Rodriguez +7
Obtaining the magnetic field vector accurately in the solar atmosphere is essential for studying changes in field topology during flares and to reliably model space weather. We tac…
ALMA observations of transient heating in a solar active region
J. M. da Silva Santos, J. de la Cruz Rodríguez, S. M. White +3
We aim to investigate the temperature enhancements and formation heights of impulsive heating phenomena in solar active-regions such as Ellerman bombs (EBs), ultraviolet bursts (UV…
Stratification of canopy magnetic fields in a plage region. Constraints from a spatially-regularized weak-field approximation method
R. Morosin, J. de la Cruz Rodriguez, G. J. M. Vissers +1
The role of magnetic fields in the chromospheric heating problem remains greatly unconstrained. Most theoretical predictions from numerical models rely on a magnetic configuration,…
High-resolution observations of the solar photosphere, chromosphere and transition region. A database of coordinated IRIS and SST observations
L. H. M. Rouppe van der Voort, B. De Pontieu, M. Carlsson +30
NASA's Interface Region Imaging Spectrograph (IRIS) provides high resolution observations of the solar atmosphere through UV spectroscopy and imaging. Since the launch of IRIS in J…
Dissecting bombs and bursts: non-LTE inversions of low-atmosphere reconnection in SST and IRIS observations
G. J. M. Vissers, J. de la Cruz Rodriguez, T. Libbrecht +3
Ellerman bombs and UV bursts are transient brightenings that are ubiquitously observed in the lower atmospheres of active and emerging flux regions. Here we present inversion resul…
Automating Ellerman bomb detection in ultraviolet continua
Gregal J. M. Vissers, Luc H. M. Rouppe van der Voort, Robert J. Rutten
Ellerman bombs are transient brightenings in the wings of H-alpha 6563 Å that pinpoint photospheric sites of magnetic reconnection in solar active regions. Their partial visibility…
Solar ultraviolet bursts
Peter R. Young, Hui Tian, Hardi Peter +16
The term "ultraviolet (UV) burst" is introduced to describe small, intense, transient brightenings in ultraviolet images of solar active regions. We inventorize their properties an…
Intermittent reconnection and plasmoids in UV bursts in the low solar atmosphere
L. Rouppe van der Voort, B. De Pontieu, G. B. Scharmer +9
Magnetic reconnection is thought to drive a wide variety of dynamic phenomena in the solar atmosphere. Yet the detailed physical mechanisms driving reconnection are difficult to di…
Observing the formation of flare-driven coronal rain
E. Scullion, L. Rouppe Van Der Voort, P. Antolin +4
Flare-driven coronal rain can manifest from rapidly cooled plasma condensations near coronal loop-tops in thermally unstable post-flare arcades. We detect 5 phases that characteris…
Reconnection brightenings in the quiet solar photosphere
Luc H. M. Rouppe van der Voort, Robert J. Rutten, Gregal J. M. Vissers
We describe a new quiet-Sun phenomenon which we call "Quiet-Sun Ellerman-like Brightenings" (QSEB). QSEBs are similar to Ellerman bombs (EB) in some respects but differ significant…
Evidence for a Transition Region response to penumbral microjets in sunspots
Gregal J. M. Vissers, Luc H. M. Rouppe van der Voort, Mats Carlsson
Penumbral microjets are short-lived, fine-structured and bright jets that are generally observed in chromospheric imaging of the penumbra of sunspots. Here we investigate their pot…
Ellerman bombs at high resolution III. Simultaneous observations with IRIS and SST
Gregal J. M. Vissers, Luc H. M. Rouppe van der Voort, Robert J. Rutten +2
Ellerman bombs are transient brightenings of the extended wings of the solar Balmer lines in emerging active regions. We describe their properties in the ultraviolet lines sampled…
Ellerman bombs at high resolution. IV. Visibility in Na I and Mg I
R. J. Rutten, L. H. M. Rouppe van der Voort, G. J. M. Vissers
Ellerman bombs are transient brightenings of the wings of the solar Balmer lines that mark reconnection in the photosphere. Ellerman noted in 1917 that he did not observe such brig…
The multi-thermal and multi-stranded nature of coronal rain
P. Antolin, G. Vissers, T. M. D. Pereira +2
In this work, we analyse coordinated observations spanning chromospheric, TR and coronal temperatures at very high resolution which reveal essential characteristics of thermally un…
Ellerman Bombs at high resolution: II. Visibility, triggering and effect on upper atmosphere
Gregal J. M. Vissers, Luc H. M. Rouppe van der Voort, Robert J. Rutten
We use high-resolution imaging spectroscopy with the Swedish 1-m Solar Telescope (SST) to study the transient brightenings of the wings of the Balmer Halpha line in emerging active…
Ellerman bombs: fallacies, fads, usage
Robert J. Rutten, Gregal J. M. Vissers, Luc H. M. Rouppe van der Voort +2
Ellerman bombs are short-lived brightenings of the outer wings of Halpha that occur in active regions with much flux emergence. We point out fads and fallacies in the extensive Ell…
Flocculent flows in the chromospheric canopy of a sunspot
Gregal Vissers, Luc Rouppe van der Voort
High-quality imaging spectroscopy in the Hα line, obtained with the CRisp Imaging SpectroPolarimeter (CRISP) at the Swedish 1-m Solar Telescope (SST) at La Palma and covering a sma…
A Sharp Look at Coronal Rain with Hinode/SOT and SST/CRISP
P. Antolin, M. Carlsson, L. Rouppe van der Voort +2
The tropical wisdom that when it is hot and dense we can expect rain might also apply to the Sun. Indeed, observations and numerical simulations have shown that strong heating at f…
Ellerman Bombs at high resolution: I. Morphological evidence for photospheric reconnection
Hiroko Watanabe, Gregal Vissers, Reizaburo Kitai +2
High-resolution imaging-spectroscopy movies of solar active region NOAA 10998 obtained with the CRisp Imaging SpectroPolarimeter (CRISP) at the Swedish 1-m Solar Telescope show ver…
Coronal rain as a marker for coronal heating mechanisms
P. Antolin, K. Shibata
Reported observations in H-alpha, Ca II H and K or or other chromospheric lines of coronal rain trace back to the days of the Skylab mission. Offering a high contrast in intensity…
On-disk counterparts of type II spicules in the Ca II 854.2 nm and Halpha lines
L. Rouppe van der Voort, J. Leenaarts, B. de Pontieu +2
Recently a second type of spicules was discovered at the solar limb with the Solar Optical Telescope (SOT) onboard the Japanese Hinode spacecraft. These previously unrecognized typ…