128 citations · 329 across the 10 of their papers we have counts for
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Cross-Calibrating Sunspot Magnetic Field Strength Measurements from the McMath-Pierce Solar Telescope and the Dunn Solar Telescope
Fraser T. Watson, Christian Beck, Matthew J. Penn +3
In this article we describe a recent effort to cross-calibrate data from an infrared detector at the McMath-Pierce Solar Telescope and the Facility InfraRed Spectropolarimeter (FIR…
A Multi-Instrument Analysis of Sunspot Umbrae
Fraser T. Watson, Matthew J. Penn, William C. Livingston
The recent solar minimum and rise phase of solar cycle 24 have been unlike any period since the early 1900s. This article examines some of the properties of sunspot umbrae over the…
Variation of the Mn I 539.4 nm line with the solar cycle
S. Danilovic, S. K. Solanki, W. Livingston +2
As a part of the long-term program at Kitt Peak National Observatory (KPNO), the Mn I 539.4 nm line has been observed for nearly three solar cycles using the McMath telescope and t…
The photospheric solar oxygen project: IV. 3D-NLTE investigation of the 777 nm triplet lines
M. Steffen, D. Prakapavičius, E. Caffau +5
The solar photospheric oxygen abundance is still widely debated. Adopting the solar chemical composition based on the "low" oxygen abundance, as determined with the use of three-di…
The photospheric solar oxygen project: III. Investigation of the centre-to-limb variation of the 630nm [OI]-NiI blend
E. Caffau, H. -G. Ludwig, M. Steffen +5
The solar photospheric abundance of oxygen is still a matter of debate. For about ten years some determinations have favoured a low oxygen abundance which is at variance with the v…