Related papers: Modelling Luminous-Blue-Variable Isolation
Most stars will experience episodes of substantial mass loss at some point in their lives. For very massive stars, mass loss dominates their evolution, although the mass loss rates are not known exactly, particularly once the star has left…
We study the evolution of Lyman Break Galaxies (LBGs) from z=5 to z=0 by tracing the merger trees of galaxies in a large-scale hydrodynamic simulation based on a Lambda cold dark matter model. In particular, we emphasize on the range of…
Massive binary evolution models are needed to predict massive star populations in star forming galaxies, the supernova diversity, and the number and properties of gravitational wave sources. Such models are often computed using so called…
Eclipsing binary stars provide highly accurate measurements of the fundamental physical properties of stars. They therefore serve as stringent tests of the predictions of evolutionary models upon which most stellar age determinations are…
Characterizing multiplicity in the very low mass (VLM) domain is a topic of much current interest and fundamental importance. Here we report on a near-IR AO imaging survey of 31 young brown dwarfs and VLM stars, 28 of which are in…
The formation of massive stars is one of the major unsolved problems in stellar astrophysics. However, only few if any of these are found as single stars, on average massive stars have more than one companion. Many of them are born in dense…
We present a spectroscopic analysis of MWC 314, a luminous blue variable (LBV) candidate with an extended bipolar nebula. The detailed spectroscopic variability is investigated to determine if MWC 314 is a massive binary system with a…
The frequency of multiple systems and their properties are key constraints of stellar formation and evolution. Formation mechanisms of very low-mass (VLM) objects are still under considerable debate and an accurate assessment of their…
MWC 314 is a bright candidate luminous blue variable that resides in a fairly close binary system, with an orbital period of 60.753$\pm$0.003 d. We observed MWC 314 with a combination of optical spectroscopy, broad-band ground- and…
Blue supergiants (BSGs) are key objects for understanding the evolution of massive stars. However, discrepancies between theoretical predictions and empirical observations have opened up important questions yet to be answered. Studying…
I discuss observational clues concerning episodic mass-loss properties of massive stars in the time before the final supernova explosion. In particular, I will focus on the mounting evidence that LBVs and related stars are candidates for…
Transiting planets manifest themselves by a periodic dimming of their host star by a fixed amount. On the other hand, light curves of transiting circumbinary (CB) planets are expected to be neither periodic nor to have a single depth while…
Circumstellar disks do not evolve in isolation, as about half of solar-type stars were born in binary or multiple systems. Resolving disks in binary systems provides the opportunity to examine the influence of stellar companions on the…
Context: Field stars are not always single stars, but can often be found in bound double systems. Since binary frequencies in the birth places of stars, young embedded clusters, are sometimes even higher than on average the question arises…
New spectroscopic observations of the LBV/WR multiple system HD5980 in the Small Magellanic Cloud are used to address the question of the masses and evolutionary status of the two very luminous stars in the 19.3d eclipsing binary system.…
The formation of massive stars remains poorly understood and little is known about their birth multiplicity properties. Here, we investigate the strikingly low radial-velocity dispersion measured for a sample of 11 massive pre- and…
Context. Current implementations of mass loss for hot, massive stars in stellar evolution models include a sharp increase in mass loss when blue supergiants become cooler than Teff 20-22kK. This drastic mass-loss jump has been motivated by…
I discuss the role played by short-duration eruptive mass loss in the evolution of very massive stars. Giant eruptions of Luminous Blue Variables (LBVs) like the 19th century event of eta Carinae can remove large quantities of mass almost…
Galactic nuclei are often found to contain young stellar populations and, in most cases, a central supermassive black hole (SMBH). Most known massive stars are found in binaries or higher-multiplicity systems, and in a galactic nucleus the…
The hot massive luminous blue variables (LBVs) represent an important evolutionary phase of massive stars. Here, we report the discovery of a new LBV -- LAMOST J0037+4016 in the distant outskirt of the Andromeda galaxy. It is located in the…