Related papers: On the reliability of mass-loss-rate estimates for…

With the aim of investigating whether stellar sources can account for the >10^8 Msun dust masses inferred from mm/sub-mm observations of samples of 5<z<6.4 quasars,we develop a chemical evolution model which follows the evolution of metals…

Context: Stars evolving through the asymptotic giant branch (AGB) phase provide significant feedback to their host system, in form of both gas enriched in nuclear-burning products and dust formed in their winds, which they eject into the…

Asymptotic giant branch (AGB) stars lose their envelopes by means of a stellar wind whose driving mechanism is not understood well. Characterizing the composition and thermal and dynamical structure of the outflow provides constraints that…

We present optical high-resolution spectra of a sample of sixteen post-AGB stars and IRC +10216. Of the post-AGB stars, ten show C2 Phillips and Swan and CN Red System absorption, one CH+ emission, one CH+ absorption, and four without any…

Low- and intermediate-mass stars go through a period of intense mass-loss at the end of their lives in a phase known as the asymptotic giant branch (AGB). During the AGB a significant fraction of their initial mass is expelled in a stellar…

In this paper,we present single stellar population models of intermediate age stellar populations where dust-enshrouded AGB stars are introduced. The formation of carbon stars is also accounted for, and is taken to be a function of both…

The evolution and spectral properties of stars on the AGB are significantly affected by mass loss through dusty stellar winds. Dynamic atmosphere and wind models are an essential tool for studying these evolved stars, both individually and…

We have conducted a near-infrared monitoring campaign at the UK InfraRed Telescope (UKIRT), of the Local Group spiral galaxy M33 (Triangulum). The main aim was to identify stars in the very final stage of their evolution, and for which the…

This paper reports on computational evidence for the formation of cloud-like dust structures around C-rich AGB stars. This spatio-temporal structure formation process is caused by a radiative/thermal instability of dust forming gases as…

We review recent developments regarding radiation driven mass loss from OB-stars. We first summarize the fundamental theoretical predictions, and then compare these to observational results (including the VLT-FLAMES survey of massive…

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…

Mass loss is an important activity for red supergiants (RSGs) which can influence their evolution and final fate. Previous estimations of mass loss rates (MLRs) of RSGs exhibit significant dispersion due to the difference in method and the…

We aim to investigate mass loss and luminosity in a large sample of evolved stars in several Local Group galaxies with a variety of metalliticies and star-formation histories: the Small and Large Magellanic Cloud, and the Fornax, Carina,…

The winds observed around asymptotic giant branch (AGB) stars are generally attributed to radiation pressure on dust, which is formed in the extended dynamical atmospheres of these pulsating, strongly convective stars. Current…

[Abridged] We have computed a grid of 900 numeric dynamic model atmospheres (DMAs) using a well-tested computer code. This grid of models covers most of the expected combinations of stellar parameters, which are made up of the stellar…

We calculated theoretical evolutionary sequences of asymptotic giant branch (AGB) stars, including formation and evolution of dust grains in their circumstellar envelope. By considering stellar populations of the Large Magellanic Cloud…

We present a millimetre molecular line survey of seven high mass loss rate carbon stars in both the northern and southern skies. A total of 196 emission lines (47 transitions) from 24 molecular species were detected. The observed CO…

We study the asymptotic giant branch (AGB) evolution of stars with masses between $1~M_{\odot} - 8.5~M_{\odot}$. We focus on stars with a solar chemical composition, which allows us to interpret evolved stars in the Galaxy. We present a…

We present an extensive study of the radiative transfer in dusty galaxies based on Monte Carlo simulations. The main output of these simulations are the attenuation curves ${\cal A}_\lambda$ (i.e. the ratio between the observed, dust…

The study of post asymptotic giant branch (post-AGB) stars is a valuable tool to study still poorly known aspects of the evolution of the stars through the AGB. This is due to the accurate determination of their surface chemical composition…