204 citations · 491 across the 9 of their papers we have counts for
11 papers · 1 filter
The Quintuplet Cluster I. A K-band spectral catalog of stellar sources
A. Liermann, W. -R. Hamann, L. M. Oskinova
Three very massive clusters are known to reside in the Galactic Center region, the Arches cluster, the Quintuplet cluster and the Central parsec cluster. We obtained spectroscopic…
Puzzling X-rays from the new colliding wind binary WR65
L. M. Oskinova, W. -R. Hamann
We report the discovery of variability in the X-ray emission from the Wolf-Rayet type star WR 65. Using archival Chandra data spanning over 5 yr we detect changes of the X-ray flux…
Two extremely luminous WN stars in the Galactic center with circumstellar emission from dust and gas
A. Barniske, L. M. Oskinova, W. -R. Hamann
We study relatively isolated massive WN-type stars in the Galactic center. The K-band spectra of WR102ka and WR102c are exploited to infer the stellar parameters and to compute syn…
Phase-dependent X-ray observations of the beta Lyrae system: No eclipse in the soft band
R. Ignace, L. M. Oskinova, W. L. Waldron +2
We report on observations of the eclipsing and interacting binary beta Lyrae from the Suzaku X-ray telescope. This system involves an early B star embedded in an optically and geom…
Neglecting the porosity of hot-star winds can lead to underestimating mass-loss rates
L. M. Oskinova, W. -R. Hamann, A. Feldmeier
Context: The mass-loss rate is a key parameter of massive stars. Adequate stellar atmosphere models are required for spectral analyses and mass-loss determinations. Present models…
Quantitative X-ray spectroscopy of massive stars
L. M. Oskinova, W. -R. Hamann, A. Feldmeier
Radiative transfer in a clumped winds is used to describe X-ray emission line profiles observed in the XMM-Newton RGS spectrum of the OI star Zeta Puppis. It is shown that this X-r…