Related papers: Spectral variability of planetary nebulae and rela…
The last decade has shown us that the observational properties of neutron stars are remarkably diverse. From magnetars to rotating radio transients, from radio pulsars to `isolated neutron stars,' from central compact objects to millisecond…
We report detailed analyses of deep, high-resolution spectra of three Galactic planetary nebulae (PNe) with high abundance discrepancy factors (ADFs), Hf2-2, M1-42 and NGC6153, obtained with the Ultraviolet and Visual Echelle Spectrograph…
Stars and their exoplanets evolve together. Depending on the physical characteristics of these systems, such as age, orbital distance and activity of the host stars, certain types of star-exoplanet interactions can dominate during given…
21cm spectral-line and continuum observations of ten compact planetary nebulae have been made with the Very Large Array. Circumnebular atomic hydrogen is identified in the planetary nebulae SwSt1, M3-35, and possibly in Hu2-1. The…
Binary/multiple status can affect stars at all stages of their lifetimes: evolution onto the main sequence, properties on the main sequence, and subsequent evolution. 5 $M_\odot$ stars have provided a wealth of information about the binary…
The high luminosity of massive, early-type stars drives strong stellar winds through line scattering of the stars continuum radiation. Their momenta contribute substantially to the dynamics and energetics of the ambient interstellar medium…
Spectral analysis by means of NLTE model atmospheres has presently arrived at a high level of sophistication. High-resolution spectra of central stars of planetary nebulae can be reproduced in detail from the infrared to the X-ray…
Powerful new, high resolution, high sensitivity, multi-frequency, wide-field radio surveys such as the Australian Square Kilometre Array Pathfinder (ASKAP) Evolutionary Map of the Universe (EMU) are emerging. They will offer fresh…
We study the line widths in the [\ion{O}{3}]$\lambda$5007 and H$\alpha$ lines for two groups of planetary nebulae in the Milky Way bulge based upon spectroscopy obtained at the Observatorio Astron\'omico Nacional in the Sierra San Pedro…
Planetary nebulae have been used as tracers of light and kinematics for the stellar populations in early-type galaxies since more than twenty years. Several empirical properties have surfaced: for example the invariant bright cut-off of the…
Planetary nebulae (PNe) are an important tool for studying the dynamics and chemical evolution of galaxies in the Local Universe, given their characteristic, bright emission line spectra. The Andromeda Galaxy (M31) provides a unique…
The high mass loss rates of stars in their asymptotic giant branch (AGB) stage of evolution is one of the most important pathways for mass return from stars to the ISM. In the planetary nebulae (PNe) phase, the ejected material is…
Planetary nebulae had a double anniversary in 2014, 250 year since their discovery and 150 year since the correct spectroscopic identification. This paper gives an overview of planetary nebula research published in 2014. Topics include…
It has recently been noted that there seems to be a strong correlation between planetary nebulae with close binary central stars, and highly enhanced recombination line abundances. We present new deep spectra of seven objects known to have…
Planetary nebulae (PN) represent the evolutionary fate of the asymptotic giant branch (AGB) stellar envelopes, thus are ideally suited to study the chemical impact of AGB stars. Stellar evolution predict elemental enrichment through the AGB…
BeppoSAX observed several galactic binary X-ray pulsars during the Science Verification Phase and in the first year of the regular program. The complex emission spectra of these sources are an ideal target for the BeppoSAX instrumentation,…
We investigate Galactic bulge planetary nebulae without emission-line central stars for which peculiar infrared spectra have been obtained with the Spitzer Space Telescope, including the simultaneous signs of oxygen and carbon based dust.…
We present new imaging data and archival multiwavelength observations of the little studied emission nebula K 1-6 and its central star. Narrow-band images in H-alpha (+ [NII]) and [OIII] taken with the Faulkes Telescope North reveal a…
The planetary nebula populations of relatively nearby galaxies can be easily observed and provide both a distance estimate and a tool with which dynamical information can be obtained. Usually the requisite radial velocities are obtained by…
Close binary interactions perform a key role in the formation and shaping of planetary nebulae. However only a small fraction of Galactic planetary nebulae are known to host close binary systems. Many such systems are detectable through…