Results 111 to 120 of about 163 (129)

Mass Loss from Nuclei of Planetary Nebulae

1987
Using high resolution ultraviolet spectra taken with the IUE satellite, we study the mass loss process from the nuclei of planetary nebulae (PNN). The measured wind velocities and mass loss rates are combined with other parameters of the nuclei and the surrounding nebulae (e.g.
L. Bianchi, M. Grewing
openaire   +1 more source

The temperatures of the nuclei of high-excitation planetary nebulae

Astrophysics and Space Science, 1988
An empirical relationship between the ratio of the intensities of emission lines in spectra of planetary nebulae, 4686 Heii/Hβ andN1+N2[Oiii]/4868 Heii, is established (see Equation (1), curve in Figure 1). A new statistical temperature scale based on this empirical relationship is proposed for the determination of lower limits of the temperatures of ...
openaire   +1 more source

On planetary nebula nuclei of the spectral type 'continuous'

Publications of the Astronomical Society of the Pacific, 1994
A detailed reexamination of existing and new International Ultraviolet Explorer (IUE) low-and high-resolution spectra, plus a search of recent literature, shows that for most of the central stars of planetary nebulae the spectral classification previously called 'continuous-type' does not really exist.
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Planetary Nebulae Nuclei with White Dwarf Spectra

1991
We report here on the first results of an ongoing spectroscopic investigation of very old planetary nebulae together with their central stars, with the aim of a better understanding of the late planetary and early white dwarf evolution. We found that most of our observed planetaries have hot degenerates as their central stars, two of them being twins ...
R. Napiwotzki, D. Schönberner
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Temperatures of the Nuclei of Planetary Nebulae

Astronomische Nachrichten, 1931
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Proto-Planetary Nebulae

Annual Review of Astronomy and Astrophysics, 1993
Sun Kwok
exaly   +2 more sources

ON THE LUMINOSITIES OF THE NUCLEI OF PLANETARY NEBULAE

Publications of the Astronomical Society of the Pacific, 1927
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Planetary Nebulae and How to Find Them: A Concise Review

Frontiers in Astronomy and Space Sciences, 2022
Quentin Parker
exaly  

Galactic Planetary Nebulae With Wolf-Rayet Nuclei - II. A Consistent Observational Data Set

Astronomy and Astrophysics, 2001
G Stasińska, M Pena
exaly  

Binary Planetary Nebulae Nuclei Towards the Galactic Bulge - II. A Penchant for Bipolarity and Low-Ionisation Structures

Astronomy and Astrophysics, 2009
Quentin Parker, Brent Miszalski, A Acker
exaly