Related papers: 26Al yields from rotating Wolf--Rayet star models

Evolution of Population I stars with initial masses from 70M_\odot to 130M_\odot is considered under various assumptions on the mass loss rate \dot M. The mass-luminosity relation of W-R stars is shown to be most sensitive to the mass loss…

Wolf-Rayet (WR) stars are helium-burning, evolved massive stars which have had most of their hydrogen-rich outer layers removed either through stellar winds and/or binary stripping. Here we report on LMC173-1, a WN3+O binary located in the…

We present here the initial results of a new study of massive star yields of Fe-peak elements. We have compiled from the literature a database of carefully determined solar neighborhood stellar abundances of seven iron-peak elements, Ti, V,…

We present a new set of synthesis models for stellar populations obtained with Starburst99, which are based on new stellar evolutionary tracks with rotation. We discuss models with zero rotation velocity and with velocities of 40% of the…

We have spectroscopically identified 60 Galactic Wolf-Rayet (WR) stars, including 38 nitrogen types (WN) and 22 carbon types (WC). Using photometry from the Spitzer/GLIMPSE and 2MASS databases, the WRs were selected via a method we have…

The scale of alpha-element yields is difficult to predict from theory because of uncertainties in massive star evolution, supernova physics, and black hole formation, and it is difficult to constrain empirically because the impact of higher…

Recently acquired evidence shows that extrasolar asteroids exhibit over a factor of 100 variation in the iron to aluminum abundance ratio. This large range likely is a consequence of igneous differentiation that resulted from heating…

We study the role of radial motions of stars and gas on the evolution of abundance profiles in the Milky Way disk. We investigate, in a parametrized way, the impact of radial flows of gas and radial migration of stars induced mainly by the…

Fluorine has many different potential sites and channels of production, making narrowing down a dominant site of fluorine production particularly challenging. In this work, we investigate which sources are the dominant contributors to the…

Massive star winds are structured both stochastically ("clumps") and often coherently (Co-rotation Interaction Regions, or CIRs). Evidence for CIRs threading the winds of Wolf-Rayet (WR) stars arises from multiple diagnostics including…

In the light of the new observational data related to fluorine abundances in the solar neighborhood stars, we present here chemical evolution models testing different fluorine nucleosynthesis prescriptions with the aim to best fit those new…

The amplitude and morphology of light curves of solar-like stars change substantially with increasing rotation rate: brightness variations get amplified and become more regular, which has so far not been explained. We develop a modelling…

The comparison of COMPTEL 1.8 MeV gamma-ray line data to an extended data base of tracer maps revealed an extremely close correlation between 1.8 MeV gamma-ray line emission on the one side and 53 GHz microwave free-free emission and 158 um…

Rotating massive stars at $Z=10^{-8}$ and $10^{-5}$ lose a great part of their initial mass through stellar winds. The chemical composition of the rotationally enhanced winds of very low $Z$ stars is very peculiar. The winds show large CNO…

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 a framework for the computation of effective stellar yields that accounts for a mixed population of binary and single stars under an adjustable mix of binary evolution settings: the binary fraction, the accretion efficiencies of…

We update the treatment of chemical evolution in the Munich semi-analytic model, L-GALAXIES. Our new implementation includes delayed enrichment from stellar winds, supernovae type II (SNe-II) and supernovae type Ia (SNe-Ia), as well as…

Evolutionary models of massive stars are quasi-exclusively computed using an Eddington gray atmosphere. This approximation does not accurately describe the complex physical phenomena occurring in the atmosphere of massive stars. We aim to…

We present theoretical mass estimates of $^{26}$Al and $^{60}$Fe throughout the Galaxy, performed with a numerical chemical evolution model including detailed nucleosynthesis prescriptions for stable and radioactive nuclides. We compared…

We use a large sample of 174 Wolf-Rayet (WR) galaxies drawn from the Sloan Digital Sky Survey to study whether and how the slope of the stellar initial mass function depends on metallicity. We calculate for each object its oxygen abundance…