The post-common-envelope binary central star of the planetary nebula ETHOS 1

Abstract

We present a detailed study of the binary central star of the planetary nebula ETHOS 1 (PN G068.1+11.0). Simultaneous modelling of light and radial velocity curves reveals the binary to comprise a hot and massive pre-white-dwarf with an M-type main-sequence companion. A good fit to the observations was found with a companion that follows expected mass-temperature-radius relationships for low-mass stars, indicating that despite being highly irradiated it is consistent with not being significantly hotter or larger than a typical star of the same mass. Previous modelling indicated that ETHOS 1 may comprise the first case where the orbital plane of the central binary does not lie perpendicular to the nebular symmetry axis, at odds with the expectation that the common envelope is ejected in the orbital plane. We find no evidence for such a discrepancy, deriving a binary inclination in agreement with that of the nebula as determined by spatio-kinematic modelling. This makes ETHOS 1 the ninth post-common-envelope planetary nebula in which the binary orbital and nebular symmetry axes have been shown to be aligned, with as yet no known counter-examples. The probability of finding such a correlation by chance is now less than 0.00002%.

8 pages, 4 figures, accepted for publication in MNRAS

References in corpus (16)

• New Grids of ATLAS9 Model Atmospheres
• Physics Of Eclipsing Binaries. II. Towards the Increased Model Fidelity
• First science with SALT: peering at the accreting polar caps of the eclipsing polar SDSS J015543.40+002807.2
• Binary Planetary Nebulae Nuclei towards the Galactic Bulge. I. Sample Discovery, Period Distribution and Binary Fraction
• The Magellanic Cloud Calibration of the Galactic Planetary Nebula Distance Scale
• Binarity and the abundance discrepancy problem in planetary nebulae
• Observational Confirmation of a Link Between Common Envelope Binary Interaction and Planetary Nebula Shaping
• Identifying close binary central stars of PN with Kepler
• Gravity and limb-darkening coefficients for compact stars: DA, DB, and DBA eclipsing white dwarfs
• Proof of polar ejection fom the close-binary core of the planetary nebula Abell 63
• Post Common Envelope Binaries from SDSS - III. Seven new orbital periods
• Binary Central Stars of Planetary Nebulae Discovered Through Photometric Variability V: The Central Stars of HaTr 7 and ESO 330-9
• C/O ratios in planetary nebulae with dual-dust chemistry from faint optical recombination lines
• The planetary nebula IPHASXJ211420.0+434136 (Ou5): insights into common-envelope dynamical and chemical evolution
• Discovery of Eclipsing Binary Central Stars in the Planetary Nebulae M 3-16, H 2-29 and M 2-19
• The post-common-envelope X-ray binary nucleus of the planetary nebula NGC 2392

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• Neutron-Capture Element Abundances in Planetary Nebulae