Related papers: Methods for determining AGB mass loss rates based …
The aim of this work is to use full evolutionary models to derive observational constraints on the mass loss rate of the upper Asymptotic Giant Branch (AGB) stars. The observations used to constrain the models are the relative number of…
The effect of metallicity on the AGB mass loss is reviewed. Observations have mainly been limited to the Magellanic Clouds but are observationally feasible throughout the Local Group. Expansion velocities are predicted to depend strongly on…
Context: AGB stars lose a large percentage of their mass in a dust-driven wind. This creates a circumstellar envelope, which can be studied through thermal dust emission and molecular emission lines. In the case of high mass-loss rates,…
With the advent of space missions, like SPITZER and ASTRO-F, with sensitive detectors in the near- and mid-infra red covering a reasonable field-of-view and having a good spatial resolution, it will be possible to detect individual AGB…
High rates of stable mass transfer likely occur for some binary star systems, but the resulting flow of mass and angular momentum (AM) is unclear. We perform hydrodynamical simulations of a polytropic donor star and a point mass secondary…
Using a radiative transfer code (DUSTY) parameters of the circumstellar dust shells of 15 hot post-AGB stars have been derived. Combining the optical, near and far-infrared (ISO, IRAS) data of the stars, we have reconstructed their spectral…
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…
Mass-loss rates from hot, massive stars are important for a range of astrophysical applications. We present \href{https://lime.ster.kuleuven.be/}{LIME}, a fast, efficient, and easy-to-use real-time mass-loss calculator for line-driven winds…
An extensive radiative transfer analysis of circumstellar SiO `thermal' radio line emission from a large sample of M-type AGB stars has been performed. The sample contains 18 irregulars of type Lb (IRV), 7 and 34 semiregulars of type SRa…
Atmospheres of evolved AGB stars are heavily affected by pulsation, dust formation and mass loss, and they can become very extended. Time series of observed high-resolution spectra proved to be a useful tool to study atmospheric dynamics…
We explore one of plausible causes of asymmetry in the wind of an AGB star - the presence of a binary companion. We have developed a simple method for estimating the intrinsic non-sphericity of the outflow in that case. Assuming the Roche…
In this note I present an outline of infrared (IR) photometric AGB properties, based on two samples of Galactic Long Period Variables (C- and S-type respectively). I show the various selection criteria used during the choice of the sources…
The mass loss experienced on the asymptotic giant branch (AGB) at the end of the lives of low- and intermediate-mass stars is widely accepted to rely on radiation pressure acting on dust grains formed in the extended AGB atmospheres. The…
Observational and theoretical arguments suggest that the momentum carried in mass outflows from AGN can reach several times L / c, corresponding to outflow rates of hundreds of solar masses per year. Radiation pressure on lines alone may…
[Abridged] Aim: We aim to derive a new mass-loss rate prescription for RSGs that is not afflicted with some uncertainties inherent in preceding studies. Methods: We have observed CO rotational line emission towards a sample of RSGs in the…
Recent observations from the Spitzer Space Telescope enable us to study the mid-infrared dust excess of Asymptotic giant branch (AGB) stars in the Large Magellanic Cloud (LMC). Using mid-infrared spectra, together with photometric data from…
Radial velocity studies of accreting binary stars commonly use accretion disk emission lines to determine the radial velocity of the primary star and therefore the mass ratio. These emission line radial velocity curves are often shifted in…
We have observed five carbon-rich AGB stars in the Fornax dwarf spheroidal (dSph) galaxy, using the Infrared Spectrometer on board the Spitzer Space Telescope. The stars were selected from a near-infrared survey of Fornax and include the…
Molecules and dust produced by the atmospheres of cool evolved stars contribute to a significant amount of the total material found in the interstellar medium. To understand the mechanism behind the mass loss of these stars, it is of…
Calculating abundance stratifications in ApBp/HgMn star atmospheres, we are considering mass-loss in addition to atomic diffusion in our numerical code in order to achieve more realistic models. These numerical simulations with mass-loss…