260 citations · 349 across the 5 of their papers we have counts for
5 papers
A time-series VI study of the variable stars of the globular cluster NGC 6397
J. A. Ahumada, A. Arellano Ferro, I. Bustos Fierro +4
We present a new time-series VI CCD photometry of the globular cluster NGC 6397, from which we obtained and analysed the light curves of 35 variables carefully identified in the cl…
A celestial matryoshka: Dynamical and spectroscopic analysis of the Albireo system
Ronald Drimmel, Alessandro Sozzetti, Klaus-Peter Schroeder +4
We present a spectroscopic characterisation and a new orbital solution for the binary system beta Cyg Aa/Ac (MCA 55), the primary component (beta Cyg A) of the well-known wide doub…
The Basal Chromospheric Mg II h+k Flux of Evolved Stars: Probing the Energy Dissipation of Giant Chromospheres
M. I. Perez Martinez, K. -P. Schroeder, M. Cuntz
Of a total of 177 cool G, K, and M giants and supergiants, we measured the Mg II h+k line emission of extended chromospheres in high-resolution (LWR) IUE spectra by using the IUE f…
Rings and Halos in the Mid-Infrared: The Planetary Nebulae NGC 7354 and NGC 3242
J. P. Phillips, G. Ramos-Larios, K. -P. Schroeder +1
We present images of the planetary nebulae (PNe) NGC 7354 and NGC 3242 in four mid-infrared (MIR) photometric bands centred at 3.6, 4.5, 5.8 and 8.0 microns; the results of observa…
A New Version of Reimers' law of Mass Loss Based on a Physical Approach
K. -P. Schroeder, M. Cuntz
We present a new semi-empirical relation for the mass loss of cool stellar winds, which so far has frequently been described by "Reimers' law". Originally, this relation was based…