Related papers: A Census of B[e] Supergiants
Mass-loss rates are one of the most relevant parameters determining the evolution of massive stars. In particular, the rates at which the star loses mass during the red-supergiant (RSG) phase is the least constrained by the observations or…
Stars and planets form, live, and evolve in unison. Throughout the life of a star, dusty circumstellar discs and stellar outflows influence the further evolution of both the star(s) and their orbiting planet(s). Planet-forming discs, winds…
The majority of stars more massive than the Sun is found in binary or multiple star systems and many of them will interact during their evolution. Specific interactions, where progenitors and post-mass transfer (MT) systems are clearly…
Massive stars have a profound influence on the Universe, but their formation remains poorly understood. We review the current status of observational and theoretical research in this field, describing the various stages of an evolutionary…
The most massive stars, with initial masses above ~50M_sun, encounter a phase of extreme mass loss - sometimes accompanied by so-called giant eruptions - in which the stars' evolution is reversed from a redward to a blueward motion in the…
A sample of 97 galactic field Be stars were studied by taking into account the effects induced by the fast rotation on their fundamental parameters. All program stars were observed in the BCD spectrophotometric system in order to minimize…
Those massive stars that, during their deaths, give rise to gamma-ray bursts (GRBs) must be endowed with an unusually large amount of angular momentum in their inner regions, one to two orders of magnitude greater than the ones that make…
Stellar-mass black holes (BHs), with masses comparable to stars, are a major constituent of our Milky Way galaxy. This chapter describes the landscape of challenging, and long-sought efforts to identify these objects in the Galaxy. The…
Recent stellar evolution computations indicate that massive stars in the range ~ 20 - 30 Msun are located in the blue supergiant (BSG) region of the Hertzsprung-Russell diagram at two different stages of their life: immediately after the…
The evolution of massive stars is affected by a variety of physical processes including convection, rotation, mass loss and binary interaction. Because these processes modify the internal chemical abundance profiles in multiple ways…
In spite of significant recent and ongoing research efforts, most of the early evolution and long-term fate of young massive star clusters remain clouded in uncertainties. Here, I discuss our understanding of the initial conditions of star…
Intense mass loss through cool, low-velocity winds is a defining characteristic of low-to-intermediate mass stars during the asymptotic giant branch (AGB) evolutionary stage. Such winds return up ~80% of the initial stellar mass to the…
Despite their paucity, massive hot stars are real cosmic engines of fundamental importance in shaping our Universe, from its very early stages up to its current appearance. Understanding the physics of massive stars is then a key issue for…
The evolution of central stars of planetary nebulae can proceed in several distinct ways, either leading to H-deficiency or to H-normal surface composition. Several new simulations of the evolution channels that lead to H-deficiency are now…
In this review I first summarize why binaries are key objects in the study of stellar populations, key objects to understand the evolution of star clusters, key objects to understand galaxies and thus the universe. I then focus on 4…
Observations of star-forming galaxies in the distant Universe (z > 2) are starting to confirm the importance of massive stars in shaping galaxy emission and evolution. Inevitably, these distant stellar populations are unresolved, and the…
Massive stars expel large amounts of mass during their late evolutionary phases. We aim to unveil the physical conditions within the warm molecular environments of B[e] supergiants (B[e]SGs) and yellow hypergiants (YHGs), which are known to…
In spite of the almost all-encompassing variability of Be stars, surveys play a steadily increasing role in complementing the insights gained from single-star studies. The definition of classical Be stars as recently augmented by…
Stellar evolution models of massive stars are very sensitive to the adopted mass-loss scheme. The magnitude and evolution of mass-loss rates significantly affect the main sequence evolution, and the properties of post-main sequence objects,…
Red supergiants (RSGs) are an evolved stage in the life of intermediate massive stars (than than 25 solar masses). For many years, their location in the H-R diagram was at variance with the evolutionary models. Using the MARCS stellar…