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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 wavelength range. In the case of LSV +4621, the exciting star of Sh 2-216, we demonstrate the state-of-the-art in the determination of photospheric properties like, e.g., effective temperature, surface gravity, and abundances of elements from hydrogen to nickel. From such detailed model atmospheres, we can reliably predict the ionizing spectrum of a central star which is a necessary input for the precise analysis of its ambient nebula. NLTE model-atmosphere spectra, however, are not only accessible for specialists. In the framework of the German Astrophysical Virtual Observatory (GAVO), we provide pre-calculated grids of tables with synthetic spectra of hot, compact stars as well as a tool to calculate individual model-atmosphere spectra in order to make the use of synthetic stellar spectra as easy as the use of blackbody flux distributions had been in the last century.
Context. At least 492 central stars of Galactic planetary nebulae (CSPNs) have been assigned spectral types. Since many CSPNs are faint, these classification efforts are frequently made at low spectral resolution. However, the stellar Balmer absorpti
Context. There are more than 3000 true and probable known Galactic Planetary Nebulae (PNe), but only for 13% of them there is central star spectroscopic information available. Aims. To contribute to the knowledge of central stars of planetary nebulae
While most of the low-mass stars stay hydrogen-rich on their surface throughout their evolution, a considerable fraction of white dwarfs as well as central stars of planetary nebulae have a hydrogen-deficient surface composition. The majority of thes
The age distribution of the central stars of planetary nebulae (CSPN) is estimated using two methods based on their kinematic properties. First, the expected rotation velocities of the nebulae at their Galactocentric distances are compared with the p
Trigonometric parallaxes of 16 nearby planetary nebulae are presented, including reduced errors for seven objects with previous initial results and results for six new objects. The median error in the parallax is 0.42 mas, and twelve nebulae have par