Physico-chemical spectroscopic mapping of the planetary nebula NGC 40 and the 2D_NEB, a new 2D algorithm to study ionised nebulae

Abstract

In this paper we present an analysis of the physical and chemical conditions of the planetary nebula NGC 40 through spatially-resolved spectroscopic maps. We also introduce a new algorithm --2D_NEB-- based on the well-established IRAF nebular package, which was developed to enable the use of the spectroscopic maps to easily estimate the astrophysical quantities of ionised nebulae. The 2D_NEB was benchmarked, and we clearly show that it works properly, since it compares nicely with the IRAF nebular software. Using this software, we derive the maps of several physical parameters of NGC 40. From these maps, we conclude that Te[NII] shows only a slight temperature variation from region to region, with its values constrained between ~8,000 K and ~9,500 K. Electron densities, on the other hand, have a much more prominent spatial variation, as Ne[SII] values vary from ~1,000 cm^(-3) to ~3,000 cm^(-3). Maps of the chemical abundances also show significant variations. From the big picture of our work, we strongly suggest that analysis with spatial resolution be mandatory for more complete study of the physical and chemical properties of planetary nebulae.

15 pages, 10 figures, 8 tables; Accepted for publication in MNRAS

References in corpus (6)

• Integral field spectroscopy of planetary nebulae: mapping the line diagnostics and hydrogen-poor zones with VLT FLAMES
• A self-consistent stellar and 3D nebular model for Planetary Nebula IC418
• The Iron abundance in Galactic Planetary Nebulae
• On the nitrogen abundance of FLIERs: the outer knots of the planetary nebula NGC 7009
• X-ray Imaging of Planetary Nebulae with Wolf-Rayet-type Central Stars: Detection of the Hot Bubble in NGC 40
• 3-D Photoionization Structure and Distances of Planetary Nebulae III. NGC 6781

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• Spectroscopic Analysis Tool for intEgraL fieLd unIt daTacubEs (satellite): Case studies of NGC 7009 and NGC 6778 with MUSE
• AMI observations of unmatched Planck ERCSC LFI sources at 15.75 GHz
• Adjusting the bow-tie: A morpho-kinematic study of NGC40
• The Effect of the Slit Configuration on the H${}_2$ 1-0~S(1) to Br$\gamma$ Line Ratio of Spatially Resolved Planetary Nebulae