相关论文: Orbital elements of barium stars formed through a …
Adpoting new s-process nucleosynthesis scenario and branch s-process path, we calculate the heavy-element abundances and C/O ratio of solar metallicity 3M_sun TP-AGB stars. The evolutionary sequence from M to S to C stars of AGB stars is…
We examine the composition of barium stars in the context of mass transfer from an asymptotic giant branch (AGB) companion. We accrete between 0.01 and 0.5 M$_\odot$ of AGB ejecta on to low mass companions of [Fe/H] = -0.25 at the ages…
Using 3D radiation-hydrodynamic simulations and analytic theory, we study the orbital evolution of asymptotic-giant-branch (AGB) binary systems for various initial orbital separations and mass ratios, and thus different initial accretion…
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…
The formation mechanism of the barium stars is thought to be well understood. Barium-rich material, lost in a stellar wind from a thermally-pulsing asymptotic-giant branch star in a binary system, is accreted by its companion main-sequence…
Barium stars are extrinsic Asymptotic Giant Branch (AGB) stars. They present the s-enhancement characteristic for AGB and post-AGB stars, but are in an earlier evolutionary stage (main sequence dwarfs, subgiants, red giants). They are…
Smoothed particle hydrodynamics (SPH) is used to estimate accretion rates of mass, linear and angular momentum in a binary system where one component undergoes mass loss through a wind. Physical parameters are chosen such as to model the…
Interacting binaries are of general interest as laboratories for investigating the physics of accretion, which gives rise to the bulk of high-energy radiation in the Galaxy. They allow us to probe stellar evolution processes that cannot be…
Wind mass transfer in binary systems with AGB donor stars plays a fundamental role in the formation of a variety of objects, including barium stars and CEMP stars. We carry out a comprehensive set of SPH simulations of wind-losing AGB stars…
We study the formation, evolution and physical properties of accretion disks formed via wind capture in binary systems. Using the AMR code AstroBEAR, we have carried out high resolution 3D simulations that follow a stellar mass secondary in…
Carbon-enhanced metal-poor stars, CH stars and barium stars, among other classes of chemically peculiar stars, are thought to be products of the interaction of low- and intermediate-mass binaries which occurred when the most evolved star…
As stars evolve, they undergo significant changes in their physical properties, which can have a profound impact on the planets orbiting them. In particular, the mass lost through stellar wind may be partially accreted by orbiting planets.…
We study the dynamical effects of gravitational focusing by a binary companion on winds from late-type stars. In particular, we investigate the mass transfer and formation of accretion disks around the secondary in detached systems…
The chemically peculiar barium stars, CH stars, and most CEMP stars are all believed to be the products of mass transfer in binary systems from a now extinct AGB primary star. The mass of the AGB star and the orbital parameters of the…
I review the process of mass transfer in a binary system through a stellar wind, with an emphasis on systems containing a red giant. I show how wind accretion in a binary system is different from the usually assumed Bondi-Hoyle…
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…
Many binary stellar systems in which the primary star is beyond the asymptotic giant branch (AGB) evolutionary phase show significant orbital eccentricities whereas current binary interaction models predict their orbits to be circularised.…
We perform numerical simulations to investigate high-power wind accretion in massive binary systems undergoing enhanced mass-loss episodes. The primary star is taken in the mass range $M_{1} = 60$--$90\,\mathrm{M_{\odot}}$, while the…
We discuss the formation of planetary nebulae (PNe) having a pair of lobes, or multi-lobes, in their inner region surrounded by an elliptical or spherical shell or halo. We suggest that most of these PNe are formed by wide binary systems,…
Mass transfer from an evolved donor star to its binary companion is a standard feature of stellar evolution in binaries. In wide binaries, the companion star captures some of the mass ejected in a wind by the primary star. The captured…