71 citations · 704 across the 26 of their papers we have counts for
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Properties of WNh stars in the Small Magellanic Cloud: evidence for homogeneous evolution
F. Martins, D. J. Hillier, J. C. Bouret +4
We derive the physical properties of three WNh stars in the SMC to constrain stellar evolution beyond the main sequence at low metallicity and to investigate the metallicity depend…
New insights into the nature of the SMC WR/LBV binary HD 5980
C. Foellmi, G. Koenigsberger, L. Georgiev +14
We present the results of optical wavelength observations of the unusual SMC eclipsing binary system HD 5980 obtained in 1999 and 2004--2005. Radial velocity curves for the eruptin…
Recovery of p-modes in the combined 2004-2005 MOST observations of Procyon
S. V. Marchenko
Procyon A, a bright F5 IV-V Sun-like star, is justifiably regarded as a prime asteroseismological target. This star was repeatedly observed by MOST, a specialized microsatellite pr…
Spectroscopy of SMC Wolf-Rayet Stars Suggests that Wind-Clumping does not Depend on Ambient Metallicity
S. V. Marchenko, C. Foellmi, A. F. J. Moffat +3
The mass-loss rates of hot, massive, luminous stars are considered a decisive parameter in shaping the evolutionary tracks of such stars and influencing the interstellar medium on…
Dust Formation in Massive WR+O Binaries: Recent Results
Sergey V. Marchenko, Anthony F. J. Moffat
The massive, luminous Population I Wolf-Rayet stars can be considered as stars with the highest known sustained mass loss rates. Around 10% of WR stars may form carbon-rich dust in…
Origin of Structures in Wolf-Rayet Winds: FUSE Observations of WR 135
S. V. Marchenko, A. F. J. Moffat, N. St-Louis +1
We report the detection with FUSE of strong, highly blue-shifted absorption features appearing in the absorption troughs of practically all major P Cygni profiles in the presumably…
delta Ceti is not monoperiodic: seismic modeling of a beta Cephei star from MOST spacebased photometry
C. Aerts, S. V. Marchenko, J. M. Matthews +7
The beta Cephei star delta Ceti was considered one of the few monoperiodic variables in the class. Despite (or perhaps because of) its apparently simple oscillation spectrum, it ha…
Dust Production in the High-Redshift Universe
S. V. Marchenko
How much dust can be produced in the early Universe? Does dust production depend on the average heavy-metal content of the hosting galaxy? Considering supernova explosions, massive…
Wind ionization structure of the short-period eclipsing LMC Wolf-Rayet binary BAT99-129: preliminary results
C. Foellmi, A. F. J. Moffat, S. V. Marchenko
BAT99-129 is a rare, short-period eclipsing Wolf-Rayet binary in the Large Magellanic Cloud. We present here medium-resolution NTT/EMMI spectra that allow us to disentangle the spe…
The Wolf-Rayet hydrogen puzzle -- an observational point of view
C. Foellmi, S. V. Marchenko, A. F. J. Moffat
Significant amounts of hydrogen were found in very hot early-type single WN stars in the SMC and the LMC. Recently, we found similar evidence in the Wolf-Rayet star of a short-peri…
The massive eclipsing LMC Wolf-Rayet binary BAT99-129. 1 Orbital parameters, hydrogen content and spectroscopic characteristics
C. Foellmi, A. F. J. Moffat, S. V. Marchenko
BAT99-129 in the LMC is one among a handful of extra-galactic eclipsing Wolf-Rayet binaries known. We present blue, medium-resolution, phase-dependent NTT-EMMI spectra of this syst…
Stellar Model Analysis of the Oscillation Spectrum of eta Bootis Obtained from MOST
D. B. Guenther, T. Kallinger, P. Reegen +8
Eight consecutive low-frequency radial p-modes are identified in the G0 IV star eta Bootis based on 27 days of ultraprecise rapid photometry obtained by the MOST (Microvariability…
Spectroscopic study of the long-period dust-producing WC7pd+O9 binary HD192641
L. Lefevre, S. V. Marchenko, S. Lepine +12
We present the results of an optical spectroscopic study of the massive Wolf-Rayet binary WR137. These data cover the dust-formation maximum in 1997. Combining all available measur…
Differential rotation of the active G5V star Kappa1 Ceti: Photometry from the MOST satellite
Slavek M. Rucinski, Gordon A. H. Walker, Jaymie M. Matthews +8
About 30.5 days of nearly uninterrupted broadband photometry of the solar-type star Kappa1 Ceti, obtained with the MOST (Microvariability & Oscillations of STars) satellite, shows…
Large-scale wind structures in OB supergiants: a search for rotationally modulated Hαvariability
T. Morel, S. V. Marchenko, A. K. Pati +4
We present the results of a long-term monitoring campaign of the Hαline in a sample of bright OB-supergiants (O7.5-B9) that aims at detecting rotationally modulated changes potenti…
An X-ray investigation of the NGC 346 field in the SMC (2) : the field population
Y. Naze, J. M. Hartwell, I. R. Stevens +5
We present results from a Chandra observation of the NGC346 cluster, which is the ionizing source of N66, the most luminous HII region and the largest star formation region in the…
Massive Binary WR112 and Properties of Wolf-Rayet Dust
S. V. Marchenko, A. F. J. Moffat, W. D. Vacca +2
Some hot, massive, population-I Wolf-Rayet (WR) stars of the carbon subclass are known to be prolific dust-producers. How dust can form in such a hostile environment remains a myst…
Coordinated Monitoring of the Eccentric O-star Binary Iota Orionis: The X-ray Analysis
Julian Pittard, Ian Stevens, Michael Corcoran +3
We analyse two ASCA observations of the highly eccentric O9III + B1III binary Iota Orionis obtained at periastron and apastron. Based on the assumption of a strong colliding winds…
A 2.3-Day Periodic Variability in the Apparently Single Wolf-Rayet Star WR 134: Collapsed Companion or Rotational Modulation?
T. Morel, S. V. Marchenko, P. R. J. Eenens +8
We present the results of an intensive campaign of spectroscopic and photometric monitoring of the peculiar Wolf-Rayet star WR 134 from 1989 to 1997. This unprecedentedly large dat…