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Monitoring stellar orbits around the Massive Black Hole in the Galactic Center
We present the results of 16 years of monitoring stellar orbits around the massive black hole in the center of the Milky Way, using high-resolution near-infrared techniques. This work refines our
A new calibration of stellar parameters of Galactic O stars
We present new calibrations of stellar parameters of O stars at solar metallicity taking non-LTE, wind, and line-blanketing effects into account. Gravities and absolute visual magnitudes are derived
UBVJHK synthetic photometry of Galactic O stars
Aims. The development of powerful infrared observational technics enables the study of very extincted objects and young embedded star forming regions. This is especially interesting in the cont ext
O stars with weak winds: the Galactic case
We study the stellar and wind properties of a sample of Galactic O dwarfs to track the conditions under which weak winds (i.e mass loss rates lower than � 10 −8 M⊙ yr −1 ) appear. The sample is
Analysis of Galactic late-type O dwarfs: more constraints on the weak wind problem ,
Aims. We investigate the stellar and wind properties of a sample of late-type O dwarfs. Previous analyses of such stars have found very low mass-loss rates; rates much lower than predicted by theory
The MiMeS Survey of Magnetism in Massive Stars: CNO surface abundances of Galactic O stars
The evolution of massive stars is still partly unconstrained. Mass, metallicity, mass loss and rotation are the main drivers of stellar evolution. Binarity and magnetic field may also significantly
On the effective temperature scale of O stars
We rediscuss the temperature of O dwarfs based on new non-LTE line blanketed atmosphere models including stellar winds computed with the CMFGEN code of Hillier & Miller ([CITE]). Compared to the
POLLUX: a database of synthetic stellar spectra
Aims. Synthetic spectra are needed to determine fundamental stellar and wind parameters of all types of stars. They are also used for the construction of theoretical spectral libraries helpful for
Variable accretion and emission from the stellar winds in the Galactic Centre
Numerical simulations of stellar wind dynamics in the central parsec of the Galactic Centre are presented, studying in particular the accretion of gas on to Sgr A ∗ , the supermassive black hole, and the possibility of constraining the total mass-loss rate of the ‘slow-wind stars’ using near infrared observations of gas in thecentral few arcseconds is shown.
Variations in the spectral slope of Sagittarius A* during a near-infrared flare
We have observed a bright flare of Sgr A* in the near-infrared with the adaptive optics-assisted integral-field spectrometer SINFONI. Within the uncertainties, the observed spectrum is featureless