Related papers: AGB and Post-AGB Evolution: Structural and Chemica…

We report on the discovery of a new kind of thermal pulse in intermediate mass AGB stars. Deep dredge-up during normal thermal pulses on the AGB leads to the formation of a long, unburnt tail to the helium profile. Eventually the tail…

We consider whether the subset of carbon-rich asymptotic giant branch (AGB) stars that exhibit detached, expanding circumstellar shells may reveal the past histories of these stars as having undergone helium shell flashes (thermal pulses)…

Aims: To investigate variability and to model the pulsational behaviour of AGB variables in the intermediate-age LMC cluster NGC 1846. Methods: Our own photometric monitoring has been combined with data from the MACHO archive to detect 22…

The specific characteristic of the SED of serendipitously discovered post-AGB binaries, allowed us to launch a very extensive multi-wavelength study of evolved objects, selected on the basis of very specific selection criteria. Those…

The efficiency of convection in stars affects many aspects of their evolution and remains one of the key-open questions in stellar modelling. In particular, the size of the mixed core in core-He-burning low-mass stars is still uncertain and…

In low-mass binary systems, mass transfer is likely to occur via a slow and dense stellar wind when one of the stars is in the AGB phase. Observations show that many binaries that have undergone AGB mass transfer have orbital periods of…

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…

We observed mid-infrared (7.5-22 mum) spectra of AGB stars in the globular cluster 47 Tuc with the Spitzer telescope and find significant dust features of various types. Comparison of the characteristics of the dust spectra with the…

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

The mechanisms responsible for chemical depletion across diverse astrophysical environments are not yet fully understood. In this paper, we investigate chemical depletion in post-AGB/post-RGB binary stars hosting second-generation…

We present a summary of the main sites for nucleosynthesis in intermediate mass Asymptotic Giant Branch (AGB) stars. We then discuss some detailed evolutionary models and how these have been used to create a synthetic evolution code which…

Almost all stars in the 1-8 Msun range evolve through the Asymptotic Giant Branch (AGB), preplanetary nebula (PPN) and planetary nebula (PN) evolutionary phases. Most stars that leave the main sequence in a Hubble time will end their lives…

The nearby oxygen-rich AGB star L2 Pup hosts a well-studied nearly edge-on disk. To date, disks around AGB stars have not been chemically studied in detail. By combining a parameterisation commonly used for protoplanetary disks and archival…

Encoded in the time- and wavelength dependent properties of pulsating AGB stars are the underlying fundamental parameters of mass, composition and evolutionary state. However, the standard technique of placing stars on a HR diagram, even…

(abbreviated) Measuring the surface abundances of AGB stars is an important tool for studying the effects of nucleosynthesis and mixing in the interior of low- to intermediate mass stars during their final evolutionary phases. The…

Post-RGB and post-AGB binaries consist of a primary star that has recently evolved off either the RGB or AGB after losing most of its envelope, and a main-sequence companion. They are distinguished by luminosities below and above the RGB…

We have computed detailed evolution and nucleosynthesis models for super and massive AGB stars over the mass range 6.5-9.0 Msun in divisions of 0.5 Msun with metallicities Z=0.02, 0.008 and 0.004. These calculations, in which we find third…

We study the circumstellar evolution of the binary HD101584, consisting of a post-AGB star and a low-mass companion, which is most likely a post-common-envelope-evolution system. We used ALMA observations of the 12CO, 13CO, and C18O J=2-1…

Half or more of stars more massive than our Sun are orbited by a companion star in a binary system. Many binaries have short enough orbits that the evolution of both stars is greatly altered by an exchange of mass and angular momentum…

A sample of 116 Long Period Variables is studied with the aim to reveal relations between the properties of their light curves and of their evolution along the Asymptotic Giant Branch (AGB). Each light curve is carefully scrutinized and its…