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arXiv · 1401.1358

The post-common-envelope, binary central star of the planetary nebula Hen 2-11

David Jones·Henri M. J. Boffin·Brent Miszalski·Roger Wesson·Romano L. M. Corradi·Amy A. Tyndall
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Abstract

We present a detailed photometric study of the central star system of the planetary nebula Hen 2-11, selected for study because of its low-ionisation filaments and bipolar morphology - traits which have been strongly linked with central star binarity. Photometric monitoring with NTT-EFOSC2 reveals a highly irradiated, double-eclipsing, post-common-envelope system with a period of 0.609 d. Modelling of the lightcurve indicates that the nebular progenitor is extremely hot, while the secondary in the system is probably a K-type main sequence star. The chemical composition of the nebula is analysed, showing Hen 2-11 to be a medium-excitation non-Type I nebula. A simple photoionisation model is constructed determining abundance ratios of C/O and N/O which would be consistent with the common-envelope cutting short the AGB evolution of the nebular progenitor. The detection of a post-common-envelope binary system at the heart of Hen 2-11 further strengthens the link between binary progeny and the formation of axisymmetric planetary nebulae with patterns of low-ionisation filaments, clearly demonstrating their use as morphological indicators of central star binarity.

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David Jones, Henri M. J. Boffin, Brent Miszalski, Roger Wesson, Romano L. M. Corradi, Amy A. Tyndall. 2014-01-07. The post-common-envelope, binary central star of the planetary nebula Hen 2-11. https://doi.org/10.1051/0004-6361/201322797

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