Related papers: An observational test of common-envelope evolution
Most planetary nebulae (PNe) show beautiful, axisymmetric morphologies despite their progenitor stars being essentially spherical. Angular momentum provided by a close binary companion is widely invoked as the main agent that would help…
A quarter of DA white dwarfs are metal polluted, yet elements heavier than helium sink down through the stellar atmosphere on timescales of days. Hence, these white dwarfs must be currently accreting material containing heavy elements.…
We present a framework for the computation of effective stellar yields that accounts for a mixed population of binary and single stars under an adjustable mix of binary evolution settings: the binary fraction, the accretion efficiencies of…
The common envelope (CE) interaction between an expanding giant star and a compact companion typically leads to a rapid orbital decay, ending in either a merger or the formation of a close binary. However, the existence of post-red giant…
A significant fraction of massive stars are found in multiple systems. The effect of binarity on stellar evolution is poorly constrained. In particular, the role of tides and mass transfer on surface chemical abundances is not constrained…
Efforts to understand the origin and growth of massive black holes observed in the early Universe have spurred a strong interest in the evolution and fate of rapidly-accreting primordial (metal-free) stars. Here, we investigate the…
We present FOS observations of O III] 1666 A and C III] 1909 A emission in H II regions in dwarf irregular galaxies to measure C/O abundance ratios in those galaxies. We observe a continuous increase in C/O with increasing O/H over the…
Sequence E variables are close binary red giants that show ellipsoidal light variations. They are likely to terminate their red giant evolution by a common envelope (CE) event when the red giant fills its Roche lobe, and produce close…
Planetary Nebulae represent a powerful window into the evolution of low-intermediate mass stars that have undergone extensive mass-loss. The nebula manifests itself in an extremely wide variety of shapes, but exactly how the mass lost is…
While it is well known that mass transfer in binaries can pollute the surfaces of the accretors, it is still unclear whether this mechanism can reproduce the observed chemical inhomogeneities in globular clusters. We study the surface…
A project which aims to understand the abundance patterns of He, C, N, O, Ne, S, and Ar for a small sample of planetary nebulae is described. Abundance ratios of O/H, C/O, and N/O especially show a broad range relative to their solar…
Cataclysmic variables (CVs) are binaries in which a compact white dwarf accretes material from a low-mass companion star. The discovery of two planets in orbit around the CV HU Aquarii opens unusual opportunities for understanding the…
I propose that at the termination of the common envelope evolution (CEE) the companion to the giant star might launch jets that have variable directions and intensities, hence the jets shape the inner zones of the descendant nebula causing…
The common envelope (CE) phase is an important stage in binary stellar evolution. It is needed to explain many close binary stellar systems, such as cataclysmic variables, Type Ia supernova progenitors, or X-ray binaries. To form the…
Stellar mergers lead to diverse phenomena: rejuvenated blue stragglers, magnetised and peculiar stars, transients and nebulae. Using a grid of about 6000 detailed 1D binary evolution models (initial component masses of…
We present a possible evolutionary pathway to form planetary nebulae (PNe) with close neutron star (NS)-white dwarf (WD) binary central stars. By employing a comprehensive binary population synthesis technique we find that the evolution…
We extend the {\sl\,PARSEC} library of stellar evolutionary tracks by computing new models of massive stars, from 14\Msun to 350\Msun. The input physics is the same used in the {\sl\,PARSEC}~V1.1 version, but for the mass-loss rate which is…
Context: The Necklace nebula is a bipolar, post-common-envelope planetary nebula, the central star of which has been shown to have a dwarf carbon star companion. Aims: We aim to understand the origins of the Necklace and its dwarf carbon…
The last decade of observational and theoretical developments in stellar and binary evolution provides an opportunity to incorporate major improvements to the predictions from populations synthesis models. We compute the Galactic merger…
We use a combined binary evolution code including dynamical effects to study nova eruptions in a symbiotic system. Following the evolution, over $\sim10^5$ years, of multiple consecutive nova eruptions on the surface of a $1.25M_\odot$…