170 citations · 2.2k across the 102 of their papers we have counts for
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First measurement of the magnetic field on FK Com and its relation to the contemporaneous starspot locations
H. Korhonen, S. Hubrig, S. V. Berdyugina +5
In this study we present simultaneous low-resolution longitudinal magnetic field measurements and high-resolution spectroscopic observations of the cool single giant FK Com. The va…
Anti-solar differential rotation and surface flow pattern on UZ Librae
K. Vida, Zs. Kővári, M. Švanda +4
We re-investigate UZ Librae spectra obtained at KPNO in 1998 and 2000. From the 1998 data we compose 11 consecutive Doppler images using the Ca I-6439, Fe I-6393 and Fe I-6411 line…
GREGOR: the New German Solar Telescope
H. Balthasar, O. von der Lühe, F. Kneer +17
GREGOR is a new open solar telescope with an aperture of 1.5m. It replaces the former 45-cm Gregory Coude telescope on the Canary island Tenerife. The optical concept is that of a…
Challenges in optics for Extremely Large Telescope instrumentation
P. Spanò, F. M. Zerbi, C. J. Norrie +15
We describe and summarize the optical challenges for future instrumentation for Extremely Large Telescopes (ELTs). Knowing the complex instrumental requirements is crucial for the…
A new concept and a preliminary design for a high resolution (HR) and very-high resolution (VHR) spectrograph for the LBT
F. M. Zerbi, P. Spano', P. Conconi +4
A way to fully exploit the large collecting area of modern 8-10m class telescopes is high resolution spectroscopy. Many astrophysical problems from planetary science to cosmology b…
The first close-up of the "flip-flop" phenomenon in a single star
H. Korhonen, S. V. Berdyugina, K. G. Strassmeier +1
We present temperature maps of the active late-type giant FK Com which exhibit the first imagining record of the ``flip-flop'' phenomenon in a single star. The phenomenon, in which…