Related papers: Post-AGB Binaries
In a previous work (Pichardo et al. 2005), we studied stable configurations for circumstellar discs in eccentric binary systems. We searched for "invariant loops": closed curves (analogous to stable periodic orbits in time-independent…
Structural and chemical changes during the AGB and post-AGB evolution are discussed with respect to two recent observational and theoretical findings. On the one hand, high-resolution infrared observations revealed details of the dynamical…
Binary fraction and orbital characteristics provide indications on the conditions of star formation, as they shed light on the environment they were born in. Multiple systems are more common in low density environments rather than in higher…
We investigate observations of circumbinary disks (CBD), to find evidence for an equilibrium eccentricity predicted by current binary accretion theory. Although stellar binary demographics in the Milky Way show no evidence for a preferred…
The origin of chemically peculiar stars and non-zero eccentricity in evolved close binaries have been long-standing problems in binary stellar evolution. Answers to these questions may trace back to an intense mass transfer during AGB…
We present the first results of a systematic search for Diffuse Interstellar Bands in a carefully selected sample of post-AGB stars observed with high resolution optical spectroscopy. These stars are shown to be ideal targets to study this…
The formation of silicates in circumstellar envelopes of stars evolving through the AGB is still debated given the uncertainties affecting stellar evolution modelling, the description of the dust formation process, and the capability of…
We study the evolution of circumstellar massive disks around the primary star of a binary system focusing on the computation of disk eccentricity. In particular, we concentrate on its dependence on the binary eccentricity. Self-gravity is…
Jets are a commonly observed phenomenon in post-asymptotic giant branch (post-AGB) binaries. Due to the orbital motion of the binary, the jet causes variable absorption in the Balmer profiles. In previous work, we have developed…
We have gathered a sample of 112 main-sequence stars with known debris disks. We collected published information and performed adaptive optics observations at Lick Observatory to determine if these debris disks are associated with binary or…
Infrared studies of asymptotic giant branch (AGB) stars are critical to our understanding of the formation of cosmic dust. In this investigation, we explore the mid-to-far-infrared emission of oxygen rich AGB star RT Virginis. This…
Circumstellar disks are characteristic for star formation and vanish during the first few Myr of stellar evolution. During this time planets are believed to form in the dense midplane by growth, sedimentation and aggregation of dust.…
[Abridged] AGB stars are significant contributors to the metal enrichment of the interstellar medium. In this paper, we adapted models from advanced RHD simulations as input for radiative transfer software to create synthetic observables. A…
Circumstellar discs are expected to be the nursery of planets. Grain growth within such discs is the first step in the planet formation process in the core-accretion gas-capture scenario. We aim at providing selected criteria on…
The majority of stars more massive than the Sun is found in binary or multiple star systems and many of them will interact during their evolution. Specific interactions, where progenitors and post-mass transfer (MT) systems are clearly…
Extreme debris discs (EDDs) are bright and warm circumstellar dusty structures around main sequence stars. They may represent the outcome of giant collisions occuring in the terrestrial region between large planetesimals or planetary…
Many of the most intriguing features, including spirals and cavities, in the current disc observations are found in binary systems like GG Tau, HD 142527 or HD 100453. Such features are evidence of the dynamic interaction between binary…
Context. Binary systems can be born surrounded by circumbinary discs. The gaseous discs surrounding either of the two stellar companions can have their life extended by the supply of mass arriving from the circumbinary disc. Aims. The…
While the population of main sequence debris discs is well constrained, little is known about debris discs around evolved stars. This paper provides a theoretical framework considering the effects of stellar evolution on debris discs,…
Context: A substantial fraction of protoplanetary disks forms around stellar binaries. The binary system generates a time-dependent non-axisymmetric gravitational potential, inducing strong tidal forces on the circumbinary disk. This leads…