相关论文: Modelling predicts a molecule-rich disk around the…
The circumstellar environment of the AGB star L$_{\rm 2}$ Puppis was observed with ALMA in cycle 3, with a resolution of $15 \times 18 \rm\ mas$. The molecular emission shows a differentially rotating disk, inclined to a nearly edge-on…
Six billion years from now, while evolving on the asymptotic giant branch (AGB), the Sun will metamorphose from a red giant into a beautiful planetary nebula. This spectacular evolution will impact the Solar System planets, but…
Adaptive optics observations in the infrared (VLT/NACO, Kervella et al. 2014) and visible (VLT/SPHERE, Kervella et al. 2015) domains revealed that the nearby AGB star L2 Pup (d=64 pc) is surrounded by a dust disk seen almost edge-on.…
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…
The bright southern star L2 Pup is a particularly prominent asymptotic giant branch (AGB) star, as its distance of 64 pc makes it the nearest of its type. We report new adaptive optics observations of L2 Pup at visible wavelengths with the…
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…
Single dish observations of AGB star L$_2$ Pup have revealed exceptionally low mass loss rate and expansion velocity, challenging interpretations in terms of standard wind models. Recent VLT and ALMA observations have drawn a detailed…
Post-asymptotic giant branch (post-AGB) binaries are surrounded by massive disks of gas and dust that are similar to protoplanetary disks around young stars. We assembled a catalog of all known Galactic post-AGB binaries with disks. We…
Asymptotic giant branch (AGB) stars are significant contributors to the chemical enrichment of the interstellar medium (ISM) of galaxies. It is therefore essential to constrain the AGB contribution to the dust budget in galaxies. Recent…
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…
Emission and absorption line observations of molecules in late-type stars are a vital component in our understanding of stellar evolution, dust formation and mass loss in these objects. The molecular composition of the gas in the…
The chemical composition of a protoplanetary disk is determined not only by in situ chemical processes during the disk phase, but also by the history of the gas and dust before it accreted from the natal envelope. In order to understand the…
We calculate the physical structure of protoplanetary disks by evaluating the gas density and temperature self-consistently and solving separately for the dust temperature. The effect of grain growth is taken into account by assuming a…
The origin and evolution of chemical elements in the Universe are governed not only by nucleosynthesis processes in stars, but also by mechanisms that alter observed photospheric compositions. Among these, chemical depletion (underabundance…
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 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…
The dusty winds of cool evolved stars are a major contributor of the newly synthesised material enriching the Galaxy and future generations of stars. However, the details of the physics and chemistry behind dust formation and wind launching…
The stellar content of the nearby SB(s)m galaxy NGC 55 is investigated using images covering the visible and near-infrared wavelength regions. A well-defined plume, which stellar evolution models suggest contains stars with masses near the…
In this paper we review recent progress in our understanding of the chemical evolution of protoplanetary disks. Current observational constraints and theoretical modeling on the chemical composition of gas and dust in these systems are…
Until now, axisymmetric, alpha-disc models have been adopted for calculations of the chemical composition of protoplanetary discs. While this approach is reasonable for many discs, it is not appropriate when self-gravity is important. In…