110 citations · 1.3k across the 74 of their papers we have counts for
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Properties of the inner penumbral boundary and temporal evolution of a decaying sunspot
M. Benko, S. J. González Manrique, H. Balthasar +3
It was empirically determined that the umbra-penumbra boundaries of stable sunspots are characterized by a constant value of the vertical magnetic field. We analyzed the evolution…
Spiral-shaped wavefronts in a sunspot umbra
T. Felipe, C. Kuckein, E. Khomenko +1
Solar active regions show a wide variety of oscillatory phenomena. The presence of the magnetic field leads to the appearance of several wave modes, whose behavior is determined by…
The effects of stellar activity on optical high-resolution exoplanet transmission spectra
Paul Wilson Cauley, Christoph Kuckein, Seth Redfield +4
Chromospherically sensitive atomic lines display different spectra in stellar active regions, spots, and the photosphere, raising the possibility that exoplanet transmission spectr…
Temporal evolution of arch filaments as seen in He I 10830 Å
S. J. González Manrique, C. Kuckein, M. Collados +7
We study the evolution of an arch filament system (AFS) and of its individual arch filaments to learn about the processes occurring in them. We observed the AFS at the GREGOR solar…
Height variation of the cutoff frequency in a sunspot umbra
T. Felipe, C. Kuckein, I. Thaler
In the solar atmosphere, the acoustic cutoff frequency is a local quantity which depends on the atmospheric height. It separates the low-frequency evanescent waves from the high-fr…
Photospheric Magnetic Fields of the Trailing Sunspots in Active Region NOAA 12396
M. Verma, H. Balthasar, C. Denker +27
The solar magnetic field is responsible for all aspects of solar activity. Sunspots are the main manifestation of the ensuing solar activity. Combining high-resolution and synoptic…
Inference of magnetic fields in the very quiet Sun
M. J. Mart\' inez González, A. Pastor Yabar, A. Lagg +29
We present high-precision spectro-polarimetric data with high spatial resolution (0.4) of the very quiet Sun at 1.56m obtained with the GREGOR telescope to shed some light o…
Spectropolarimetric Observations of an Arch Filament System with GREGOR
H. Balthasar, P. Gömöry, S. J. González Manrique +16
We observed an arch filament system (AFS) in a sunspot group with the GREGOR Infrared Spectrograph attached to the GREGOR solar telescope. The AFS was located between the leading s…
High-Cadence Imaging and Imaging Spectroscopy at the GREGOR Solar Telescope - A Collaborative Research Environment for High-Resolution Solar Physics
C. Denker, C. Kuckein, M. Verma +7
In high-resolution solar physics, the volume and complexity of photometric, spectroscopic, and polarimetric ground-based data significantly increased in the last decade reaching da…
Image Quality in High-resolution and High-cadence Solar Imaging
C. Denker, E. Dineva, H. Balthasar +4
Broad-band imaging and even imaging with a moderate bandpass (about 1 nm) provides a "photon-rich" environment, where frame selection ("lucky imaging") becomes a helpful tool in im…
High-resolution imaging and near-infrared spectroscopy of penumbral decay
M. Verma, C. Denker, H. Balthasar +9
Combining high-resolution spectropolarimetric and imaging data is key to understanding the decay process of sunspots as it allows us scrutinizing the velocity and magnetic fields o…
Counter-streaming flows in a giant quiet-Sun filament observed in the extreme ultraviolet
A. Diercke, C. Kuckein, M. Verma +1
A giant solar filament was visible on the solar surface from 2011 Nov. 8-23. The filament stretched over more than half a solar diameter. Multiwavelength data from the SDO instrume…