Preliminary results of new high-resolution and S/N ratio spectra of central stars of planetary nebulae (CSPN) are presented. The atmospheric parameters (Teff...
Non-detection of Magnetic Fields in the Central Stars of the Planetary Nebulae NGC 1360 and LSS 1362
The presence of magnetic fields is an attractive hypothesis for shaping planetary nebulae (PNe). We report on observations of the central star of the two PNe...
Non-detection of the 1.67 micron band in HB 5? Implications for PAH-related models
In this paper we present a high resolution IR spectrum of the planetary nebula Hb5, over the range 1.6-1.75 micron. Our aim is to test the hypothesis invoking...
Observational Confirmation of a Link Between Common Envelope Binary Interaction and Planetary Nebula Shaping
A current issue in the study of planetary nebulae with close binary central stars (CSs) is the extent to which the binaries affect the shaping of the nebulae...
On central star luminosities and optical thicknesses in planetary nebulae
Results of an investigation of 23 planetary nebulae whose post-AGB central stars have been previously analyzed using direct spectroscopic non-LTE methods are...
On the Chemical Abundances of Multiple-Shell Planetary Nebulae with Halos
We present narrowband imagery and long-slit intermediate-resolution spectroscopy of the multiple-shell planetary nebulae NGC 2438 and NGC 5882. A comparative...
On the Detectability of Post-common-envelope Binary Central Stars of Planetary Nebulae
Common envelope evolution is widely accepted as the principal shaping agent in the formation of aspherical planetary nebulae. However, only some 20% of...
On The Kinematics of Multiple-Shell Planetary Nebulae. I. Data and Expansion Velocities
We present spatially resolved echelle spectroscopy, obtained at high spectral resolution, for 15 multiple-shell planetary nebulae. Most exhibit faint detached...
Context. The planetary nebula luminosity function (PNLF) is a standard candle that comprises a key rung on the extragalactic distance ladder. The method is...