Related papers: The missing mass conundrum of post-common-envelope…
Understanding post-common-envelope evolution is important in the studies of close-binary systems. The majority of all interacting binaries with a compact object in their system (e.g. cataclysmic variables, X-ray binaries) are thought to…
Planetary nebulae (PNe) have three main components: a central star (CS), ionised gas and dust in the nebula. Each of them contains critical chemical fingerprints of their evolution, serving as tracers of the evolution, nucleosynthesis and…
We present new analytical solutions for the dynamics of planetary nebulae. These equations consider the temporal variation of the mechanical luminosity as well as the common envelope evolution scenario. By comparing a database of nebulae…
It is widely believed that central star binarity plays an important role in the formation and evolution of aspherical planetary nebulae, however observational support for this hypothesis is lacking. Here, we present the most recent results…
Planetary nebulae are thought to be formed when a slow wind from the progenitor giant star is overtaken by a subsequent fast wind generated as the star enters its white dwarf stage$^{1}$. A shock forms near the boundary between the winds,…
We propose a scenario where a companion that is about to exit a common envelope evolution (CEE) with a giant star accretes mass from the remaining envelope outside its deep orbit and launches jets that facilitate the removal of the…
Binarity has been hypothesised to play an important, if not ubiquitous, role in the formation of planetary nebulae (PNe). Yet there remains a severe paucity of known binary central stars required to test the binary hypothesis and to place…
Preplanetary nebulae and planetary nebulae are evolved, mass-losing stellar objects that show a wide variety of morphologies. Many of these nebulae consist of outer structures that are nearly spherical (spiral/shell/arc/halo) and inner…
Interaction with the Interstellar Medium (ISM) cannot be ignored in understanding planetary nebula (PN) evolution and shaping. In an effort to understand the range of shapes observed in the outer envelopes of PNe, we have run a…
Planetary nebulae retain the signature of the nucleosynthesis and mixing events that occurred during the previous AGB phase. Observational signatures complement observations of AGB and post-AGB stars and their binary companions. The…
Modelling dust formation in single stars evolving through the carbon-star stage of the asymptotic giant branch (AGB) reproduces well the mid-infrared colours and magnitudes of most of the C-rich sources in the Large Magellanic Cloud (LMC),…
We examine the images of hundreds of planetary nebulae (PNe) and find that for about one in six PNe the morphology is too `messy' to be accounted for by models of stellar binary interaction. We speculate that interacting triple stellar…
In this paper, a time-dependent magnetohydrodynamic model is presented which aimed at understanding the superwind production by an evolved AGB star and the consecutive formation of a dense circumstellar envelope around it. We know…
While in the past spherodicity was assumed, and still is used in modeling of most nebulae, we know now that only a small number of planetary nebulae (PNe) are really spherical or at least nearly round. Round planetary nebulae are the…
We reproduce the expansion velocity--radius ($V_{\rm{exp}}$--$R_{\rm{n}}$) relation in planetary nebulae by considering a simple dynamical model, in order to investigate the dynamical evolution and formation of planetary nebulae. In our…
The increase in discovered close binary central stars of planetary nebulae is leading to a sufficiently large sample to begin to make broader conclusions about the effect of close binary stars on common envelope evolution and planetary…
It is now clear that central star binarity plays a key role in the formation and evolution of planetary nebulae, with a significant fraction playing host to close-binary central stars which have survived one or more common envelope…
We previously determined abundances of He, C, N, O, and Ne for a sample of planetary nebulae (PNe) representing a broad range in progenitor mass and metallicity, and we now compare them with theoretical predictions of PNe abundances from a…
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,…
We study the chemical abundances of a wide sample of 142 Galactic planetary nebulae (PNe) with good quality observations, for which the abundances have been derived more or less homogeneously, thus allowing a reasonable comparison with…