Bayesian posterior classification of planetary nebulae according to the Peimbert types

Abstract

In this paper we present a re-analysis of the criteria used to characterize the Peimbert classes I, IIa, IIb, III and IV, through a statistical study of a large sample of planetary nebulae previously classified according to these groups. In the original classification, it is usual to find planetary nebulae that cannot be associated with a single type; these most likely have dubious classifications into two or three types. Statistical methods can greatly contribute in providing a better characterization of planetary nebulae groups. We use the Bayes Theorem to calculate the posterior probabilities for an object to be member of each of the types I, IIa, IIb, III and IV. This calculation is particularly important for planetary nebulae that are ambiguously classified in the traditional method. The posterior probabilities are defined from the probability density function of classificatory parameters of a well-defined sample, composed only by planetary nebulae unambiguously fitted into the Peimbert types. Because the probabilities depend on the available observational data, they are conditional probabilities, and, as new observational data are added to the sample, the classification of the nebula can be improved, to take into account this new information. This method differs from the original classificatory scheme, because it provides a quantitative result of the representativity of the object within its group. Also, through the use of marginal distributions it is possible to extend the Peimbert classification even to those objects for which only a few classificatory parameters are known.

26 pages, 4 figures, 6 tables. Accepted for publication in Astronomy and Astrophysics. Tables 1 and 6 will be available only in the online version of the Journal

References in corpus (28)

• Elemental Abundance Survey of The Galactic Thick Disk
• Stellar evolution with rotation VIII: Models at Z = 10^{-5} and CNO yields for early galactic evolution
• First stars VI - Abundances of C, N, O, Li, and mixing in extremely metal-poor giants. Galactic evolution of the light elements
• Chemical yields from low- and intermediate-mass stars: model predictions and basic observational constraints
• Evolution of asymptotic giant branch stars I. Updated synthetic TP-AGB models and their basic calibration
• The early star generations: the dominant effect of rotation on the CNO yields
• Very low metallicity massive star models: Pre-SN evolution and primary nitrogen production
• A strong case for fast stellar rotation at very low metallicities
• Temperature Bias and the Primordial Helium Abundance Determination
• Galactic Evolution of Nitrogen
• An estimate of the time variation of the O/H radial gradient from planetary nebulae
• Planetary Nebula Abundances and Morphology: Probing the Chemical Evolution of the Milky Way
• Planetary nebulae abundances and stellar evolution
• The origin of nitrogen: Implications of recent measurements of N/O in Galactic metal-poor stars
• The Correlations between Planetary Nebula Morphology and Central Star Evolution. Analysis of the Northern Galactic Sample
• Chemical abundances of planetary nebulae towards the direction of the galactic anticenter
• The formation history of the Galactic bulge
• New abundances of planetary nebulae in the Galactic Bulge
• New results on the time variation of the radial abundance gradients from planetary nebulae
• CO Isotopes in Planetary Nebulae
• Abundances of Recently Discovered Planetary Nebulae Towards the Galactic Bulge
• The Detection of 3He+ in a Planetary Nebula Using the VLA
• An estimate of the time variation of the abundance gradient from planetary nebulae II. Comparison with open clusters, cepheids and young objects
• Can the third dredge-up extinguish hot-bottom burning in massive AGB stars?
• ${}^{12}$C/${}^{13}$C ratio in planetary nebulae from the IUE archives
• The 12C/13C ratio in the Planetary Nebula NGC3242 from Hubble Space Telescope STIS observations
• Stellar Populations with ELTs
• Planetary nebulae as probes for galactic chemical evolution

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• IFU spectroscopy of Southern PNe: VII Photo-ionization modelling of intermediate excitation class objects
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• On the non-thermal kappa-distributed electrons in planetary nebulae and HII regions: the kappa index and its correlations with other nebular properties
• Physical properties of the very young PN Hen3-1357 (Stingray Nebula) based on multiwavelength observations
• H$\alpha$ fluxes and extinction distances for planetary nebulae in the IPHAS survey of the Northern Galactic Plane
• Vertical Distribution and Kinematics of Planetary Nebulae in the Milky Way
• Spectroscopic Variability of the Compact Planetary Nebula Hb 12
• The Owl and other strigiform nebulae: multipolar cavities within a filled shell
• The five axes of the Turtle: symmetry and asymmetry in NGC 6210
• Interacting planetary nebulae III: Verification and galactic population based on the measurements of Gaia EDR3
• Observations of the planetary nebula RWT 152 with OSIRIS/GTC
• An investigation of planetary nebulae accompanying PG1159 central stars, based on Gaia DR2 measurements
• Appraising the Necklace: A post-common-envelope carbon dwarf inside an apparently carbon-poor planetary nebula
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• A comparative study of O, Ne, Cl, and Ar in Hii regions and PNe of the Galactic disk: Temporal evolution of radial gradients?