Related papers: The ionization structure of multiple shell planeta…
The turbulent burning of nuclei is a common phenomenon in the evolution of stars. Here we examine a challenging case: the merging of the neon and oxygen burning shells in a 23 M$_{\odot}$ star. A previously unknown quasi-steady state is…
We simulated the million degree interstellar medium and its soft X-ray images in the disk and halo of spiral galaxies using the bipolar hypershell (BHS) model. In this model hourglass-shaped expanding shells of several kpc radii are…
Galaxy clusters trace the most massive dark matter haloes, whose shapes and orientations reflect the imprint of the cosmic large-scale tidal field. This paper introduces the Subhalo-based Halo Alignment and Projected Ellipticity (SHAPE)…
Massive stars with a core-halo structure are interesting objects for stellar physics and hydrodynamics. Using simulations for stellar evolution, radiation hydrodynamics, and radiative transfer, we study the explosion of stars with an…
We present the results of a new study of mass segregation in two-component star clusters, based on a large number of numerical N-body simulations using our recently developed dynamical Monte Carlo code. Specifically, we follow the dynamical…
We study the hypothesis of high metallicity clumps being responsible for the abundance discrepancy found in planetary nebulae between the values obtained from recombination and collisionaly excited lines. We generate grids of…
This paper is the third in a series reporting on a study of carbon abundances in a carefully chosen sample of planetary nebulae representing a large range in progenitor mass and metallicity. We make use of the IUE Final Archive database…
We use a 3D photoionization modeling tool to study the morpho-kinematic properties of the Planetary Nebula (PN) NGC 3132. We show that it is possible to reproduce the low resolution observations (spectra and images) with an ellipsoidal…
Radio continuum observations trace thermal emission of ionized plasma in planetary nebulae and bring useful information on nebular geometries. A model of homogeneous sphere or shell cannot fit the nebular spectra and brightness…
We present an analysis of the binary central star of the planetary nebula NGC 2346 based on archival data from the International Ultraviolet Explorer (IUE), and new low- and high-resolution optical spectra (3700 - 7300{\AA}). By including…
We present long-slit observations in the optical and near infrared of eight HII regions in the spiral galaxy NGC 4258. Six of the observed regions are located in the SE inner spiral arms and the other two are isolated in the northern outer…
We have studied the effect of the mass of the central star (CS) on the gas evolution during the planetary nebula (PN) phase. We have performed numerical simulations of PN formation using CS tracks for six stellar core masses corresponding…
Using a radiation-gasdynamics code the evolution of spherical planetary nebulae is followed, while taking into account the evolution of central star and the fast wind. These models show the importance of ionization fronts for the structure…
Narrow-band H$\alpha$ and [N {\sc ii}] images and high-dispersion spatially-resolved echelle spectroscopy of the planetary nebula NGC 6891 are presented. These observations show a great wealth of structures. The bright central nebula is…
We present new deep imaging and high-resolution spectroscopy of the extreme-abundance-discrepancy planetary nebula Ou 5, together with photoionization modelling aimed at probing its unusual thermal and chemical structure. The nebula…
We present a systematic study of halo characteristics in the neutron-rich isotopes 28-32Ne within the deformed relativistic Hartree-Bogoliubov theory in continuum (DRHBc). Microscopic density distributions are analyzed in coordinate space,…
Aims. The magnetic star HD148937 is the only Galactic Of?p star surrounded by a nebula. The structure of this nebula is particularly complex and is composed, from the center out outwards, of a close bipolar ejecta nebula (NGC6164/5), an…
Mass outflow generated by the dynamical feedback from massive stars is currently a topic of high interest. Using a purpose-developed analysis technique, and taking full advantage of the high kinematic and angular resolution of our…
We report the discovery of significant stellar substructure in the halo and outer disk of our nearest large galactic neighbour, M31. Our deep panoramic survey with the Isaac Newton Telescope Wide Field Camera currently maps out an area of…
Though the small-scale, low-ionization knots, filaments and jets (LISs) of planetary nebulae (PNe) are known for ~30yr, some of their observational properties are not well established. In consequence our ability to include them in the wider…