Related papers: Barium Stars: Theoretical Interpretation

Barium (Ba) stars form via mass-transfer in binary systems, and can subsequently interact with their white dwarf companion in a second stage of binary interaction. We used observations of main-sequence Ba systems as input for our…

Binary interactions dominate the evolution of massive stars, but their role is less clear for low- and intermediate-mass stars. The evolution of a spherical wind from an asymptotic giant branch (AGB) star into a nonspherical planetary…

The standard model for the operation of the s-process in asymptotic giant branch (AGB) stars predicts that low-metallicity ([Fe/H] <= -1) AGB stars should exhibit large overabundances of Pb and Bi as compared to other s-elements. Eight CH…

Intermediate mass stars (1-8 solar masses) evolve along the Asymptotic Giant Branch after completion of hydrogen and helium core burning. At the tip they lose for several ten to hundred thousand years copious amounts of mass and exhibit…

The study of the evolutionary properties of Asymptotic Giant Branch stars still presents unresolved topics. Progress in the theoretical understanding of their evolution is hampered by the difficulty to empirically explain key physical…

A considerable number of asymptotic giant branch (AGB) stars exhibit UV excess and/or X-ray emission that indicates a binary companion. AGB stars are so bright that they easily outshine their companions. This almost prevents their…

The Magellanic Clouds (MCs) offer a unique opportunity to study the stellar evolution and nucleosynthesis of massive Asymptotic Giant Branch (AGB) stars in low metallicity environments where distances are known. Rubidium is a key element to…

Stardust grains that originated in ancient stars and supernovae are recovered from meteorites and carry the detailed composition of their astronomical sites of origin. We present evidence that the majority of large ($\mu$m-sized) meteoritic…

We demonstrate that a massive asymptotic giant branch (AGB) star is a good candidate as the main source of short-lived radionuclides in the early solar system. Recent identification of massive (4-8 solar masses) AGB stars in the Galaxy,…

Stellar winds observed in asymptotic giant branch (AGB) stars are usually attributed to a combination of stellar pulsations and radiation pressure on dust. Shock waves triggered by pulsations propagate through the atmosphere, compressing…

Abell 70 (PN G038.1-25.4, hereafter A 70) is a planetary nebula (PN) known for its diamond ring appearance due a superposition with a background galaxy. The previously unstudied central star is found to be a binary consisting of a G8IV-V…

We present the results of s-process nucleosynthesis calculations for AGB stars of different metallicities and initial masses. The computations were based on previously published stellar evolutionary models that account for the III dredge up…

The enrichment in s-process elements of barium stars is known to be due to pollution by mass transfer from a companion formerly on the thermally-pulsing asymptotic giant branch (AGB), now a carbon-oxygen white-dwarf (WD). This paper…

The vast majority (>=90%) of presolar SiC grains identified in primitive meteorites are relics of ancient asymptotic giant branch (AGB) stars, whose ejecta were incorporated into the Solar System during its formation. Detailed…

S stars are late-type giants with overabundances of s-process elements. They come in two flavours depending on the presence or not of technetium (Tc), an element without stable isotopes. Intrinsic S stars are Tc-rich and genuine asymptotic…

The production of the elements heavier than iron via slow neutron captures (the s process) is a main feature of the contribution of asymptotic giant branch (AGB) stars of low mass (< 5 Msun) to the chemistry of the cosmos. However, our…

Asymptotic giant branch stars are essential contributors to the near and mid-IR emission of intermediate age (0.1-1Gyr old) stellar populations. Detecting this light sets constraints on the star formation history in galaxies and,…

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…

In 1981, the idea of a superwind that ends the life of cool giant stars was proposed. Extreme OH/IR-stars develop superwinds with the highest mass-loss rates known so far, up to a few 10^(-4) Msun/yr, informing our understanding of the…

We study a sample of post-AGB stars in the Galaxy, with known surface chemical composition and s-process enrichment. The recent determination of the luminosities of these sources, based on Gaia parallaxes, allows for the fist time a deep…