179 citations · 2.3k across the 86 of their papers we have counts for
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Surface activity of the G dwarf primary in the quaternary star system V815 Her
Zsolt Kővári, Klaus G. Strassmeier, Tamás Borkovits +4
We investigate the magnetic activity of the G dwarf primary star in the multiple system V815 Herculis. Recently, TESS Sector 26 data have revealed that V815 Her is in fact a four-s…
On the lithium abundance of the visual binary components Boo A (G8V) and Boo B (K5V)
Klaus G. Strassmeier, Matthias Steffen
A spectroscopic investigation of the lithium resonance doublet in Boo A and Boo B in terms of both abundance and isotopic ratio is presented. We obtained new =130\,000 s…
Untangling the Sources of Abundance Dispersion in Low-Metallicity Stars
Emily J. Griffith, Jennifer A. Johnson, David H. Weinberg +4
We measure abundances of 12 elements (Na, Mg, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni) in a sample of 86 metal-poor () subgiant stars in the so…
The Great Dimming of Betelgeuse: a Surface Mass Ejection (SME) and its Consequences
Andrea K. Dupree, Klaus G. Strassmeier, Thomas Calderwood +7
The bright supergiant, Betelgeuse (Alpha Orionis, HD 39801), underwent a historic optical dimming during 2020 January 27 February 13. Many imaging and spectroscopic observation…
The recurrent nova V3890~Sgr: a near-infrared and optical study of the red giant component and its environment
B. Kaminsky, A. Evans, Ya. V. Pavlenko +8
We present an analysis of the red giant component of the recurrent nova V3890 Sgr, using data obtained before and after its 2019 eruption. Its effective temperature is $T_{\rm eff}…
The Origin of Weakened Magnetic Braking in Old Solar Analogs
Travis S. Metcalfe, Adam J. Finley, Oleg Kochukhov +10
The rotation rates of main-sequence stars slow over time as they gradually lose angular momentum to their magnetized stellar winds. The rate of angular momentum loss depends on the…