Photoionization modelling of planetary nebulae – II. Galactic bulge nebulae, a comparison with literature results |
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Authors: | P. A. M. van Hoof G. C. Van de Steene |
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Affiliation: | Kapteyn Astronomical Institute, PO Box 800, 9700 AV Groningen, The Netherlands; Department of Physics and Astronomy, 177 CP Building, University of Kentucky, Lexington, KY 40506–0055, USA; European Southern Observatory, Casilla 19001, Santiago 19, Chile; Research School for Astronomy and Astrophysics, Mount Stromlo Observatory, Private Bag, Weston Creek PO, ACT 2611, Australia |
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Abstract: | We have constructed photoionization models of five galactic bulge planetary nebulae using our automatic method, which enables a fully self-consistent determination of the physical parameters of a planetary nebula. The models are constrained using the spectrum, the IRAS and radio fluxes and the angular diameter of the nebula. We also conducted a literature search for physical parameters determined with classical methods for these nebulae. Comparison of the distance-independent physical parameters with published data shows that the stellar temperatures generally are in good agreement and can be considered reliable. The literature data for the electron temperature, electron density and also for the abundances show a large spread, indicating that the use of line diagnostics is not reliable and that the accuracy of these methods needs to be improved. Comparison of the various abundance determinations indicates that the uncertainty in the electron temperature is the main source of uncertainty in the abundance determination. The stellar magnitudes predicted by the photoionization models are in good agreement with observed values. |
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Keywords: | methods: data analysis ISM: abundances planetary nebulae: general |
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