Related papers: Massive star evolution at high metallicity
The abundance evolution of galaxies depends critically on the balance between the mixing of metals in their interstellar medium, the inflow of new gas and the outflow of enriched gas. We study these processes in gas columns perpendicular to…
We propose the Wind of Fast Rotating Massive Stars scenario to explain the origin of the abundance anomalies observed in globular clusters. We compute and present models of fast rotating stars with initial masses between 20 and 120 Msun for…
The stellar winds of massive stars show large changes in mass-loss rates and terminal velocities during their evolution from O-star through the Luminous Blue Variable phase to the Wolf-Rayet phase. The luminosity remains approximately…
The evolution of single stars at low metallicity has attracted a large interest, while the effect of metallicity on binary evolution remains still relatively unexplored. We study the effect of metallicity on the number of binary systems…
Recent theoretical predictions for low metallicity massive stars predict that these stars should have drastically reduced equatorial winds (mass loss) while on the main sequence, and as such should retain most of their angular momentum.…
The winds of massive stars remove a significant fraction of their mass, strongly impacting their evolution. As a star evolves, the rate at which it loses mass changes. In stellar evolution codes, different mass-loss recipes are employed for…
We present a new empirical prescription for the mass-loss rates of carbon and oxygen sequence Wolf-Rayet stars as a function of their luminosity, surface chemical composition, and initial metallicity. The new prescription is based on…
One of the key questions in Astrophysics concerns the issue of whether there exists an upper-mass limit to stars, and if so, what physical mechanism sets this limit, which might also determine if the upper-mass limit is metallicity (Z)…
Stellar winds are one of the most important drivers of massive star evolution and a vital source of chemical, mechanical, and radiative feedback. Despite its significance, mass loss remains a major uncertainty in stellar evolution models.…
Context. Very massive clusters and regions of intense star formation such as the center of our Milky Way contain young, hydrogen-burning stars very close to the Eddington Limit. Formally classified as hydrogen-rich Wolf-Rayet stars, the…
Wolf-Rayet (WR) stars near solar metallicity are believed to be driven by radiation pressure on the UV spectral lines of metal ions. As the metallicity decreases so does the line opacity, therefore the mass-loss rate. However, since the…
Observations indicate blue globular clusters have half-light radii systematically larger than those of red globular clusters. In this paper, we test whether the different metallicity-dependent stellar evolution timescales and mass-loss…
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,…
Stars stripped of their hydrogen-rich envelopes through binary interaction are thought to be responsible for both hydrogen-poor supernovae and the hard ionizing radiation observed in low-$Z$ galaxies. A population of these stars was…
I present measurements of the projected rotational velocities of a sample of 100 early B-type main-sequence stars in the Large Magellanic Cloud. This is the first extragalactic study of the distribution of stellar rotational velocities. The…
Massive star evolutionary models generally predict the correct ratio of WC-type and WN-type Wolf-Rayet stars at low metallicities, but underestimate the ratio at higher (solar and above) metallicities. One possible explanation for this…
Understanding the radii of massive stars throughout their evolution is important to answering numerous questions about stellar physics, from binary interactions on the main sequence to the pre-supernova radii. One important factor…
An analysis of some properties of stellar models as a function of metallicity Z (and helium content Y) is presented, with special attention to those stars with metallicities higher than twice or three times solar. It is shown that the…
Elliptical galaxies probably host the most metal rich stellar populations in the Universe. The processes leading to both the formation and the evolution of such stars are discussed by means of a new multi-zone photo-chemical evolution…
We show that the observed ratio of the subtypes Ib,c and II core-collapse supernovae depends on the metallicity of the host galaxy, as expected on theoretical grounds. However, the observed relation differs considerably from expectations…