Related papers: Massive Stars in the SMC
We present modeling research work of the winds and circumstellar environments of prototypical hot and cool massive stars using advanced radiative transfer (RT) calculations. This research aims at unraveling the detailed physics of various…
We search for effects of metallicity on B and Be stars in the Small and Large Magellanic Clouds (SMC and LMC) and in the Milky Way (MW). We extend our previous analysis of B and Be stars populations in the LMC to the SMC. The rotational…
We probe the radial clumping stratification of OB stars in the intermediate and outer wind regions (r>~2 R*) to derive upper limits for mass-loss rates, and compare to current mass-loss implementation. Together with archival…
There is much debate on how high-mass star formation varies with environment, and whether the sparsest star-forming environments are capable of forming massive stars. To address this issue, we have observed eight apparently isolated OB…
Massive stars and their winds have a large influence in their environment, e.g, determining the accretion rate on to the Galactic Centre (GC) super-massive black hole Sgr A*. The winds of those stars collide and are accreted, at a rate that…
Reliable predictions of mass-loss rates are important for massive-star evolution computations. We aim to provide predictions for mass-loss rates and wind-momentum rates of O-type stars, carefully studying the behaviour of these winds as…
(abridged) The strong winds of Wolf-Rayet (WR) stars are important for the mechanical and chemical feedback of the most massive stars and determine whether they end their lives as neutron stars or black holes. In this work we investigate…
Accurate determination of mass-loss rates from massive stars is important to understanding stellar and galactic evolution and enrichment of the interstellar medium. Large-scale structure and variability in stellar winds have significant…
Context: The star cluster R136 inside the LMC hosts a rich population of massive stars, including the most massive stars known. The strong stellar winds of these very luminous stars impact their evolution and the surrounding environment. We…
The proximity & low dust extinction of the Magellanic Clouds provides an ideal environment for metal-poor massive stars to be studied in detail. The HST ULLYSES initiative has provided exquisite ultraviolet spectroscopy of a large sample of…
Low-mass stars are element factories that efficiently release their products in the final stages of their evolution by means of stellar winds. Since they are large in number, they contribute significantly to the cosmic matter cycle. To…
Aims: We study the acceleration of the stellar winds of rapidly rotating low mass stars and the transition between the slow magnetic rotator and fast magnetic rotator regimes. We aim to understand the properties of stellar winds in the fast…
High resolution optical spectra of 57 Galactic B-type supergiant stars have been analyzed to determine their rotational and macroturbulent velocities. In addition, their atmospheric parameters (effective temperature, surface gravity and…
The impact of FUSE upon the fundamental parameters of OB stars and Wolf-Rayet stars is reviewed. The stellar wind signatures available in the far-UV provide us with important additional diagnostics of effective temperature. Together with…
We examine the role of rotation on the evolution and chemical yields of very metal--poor stars. The models include the same physics, which was applied successfully at the solar $Z$ and for the SMC, in particular, shear diffusion, meridional…
We present synthetic spectra and SEDs computed along evolutionary tracks at Z=1/5 Zsun and Z=1/30 Zsun, for masses between 15 and 150 Msun. We predict that the most massive stars all start their evolution as O2 dwarfs at sub-solar…
Context. Late O-type stars at luminosities $\log L/L_\odot \lesssim 5.2$ show weak winds with mass-loss rates lower than 10$^{-8} M_\odot$ yr$^{-1}$. This implies that their photospheric layers are not strongly affected by the stellar wind.…
The main effect of axial rotation on the evolution of massive PopIII stars is to trigger internal mixing processes which allow stars to produce significant amounts of primary nitrogen 14 and carbon 13. Very metal poor massive stars produce…
Aims. Having established the binary status of nineteen O-type stars located in four Cygnus OB associations, we now determine their fundamental parameters to constrain their properties and their evolutionary status. We also investigate their…
The yellow supergiant content of nearby galaxies provides a critical test of massive star evolutionary theory. While these stars are the brightest in a galaxy, they are difficult to identify because a large number of foreground Milky Way…