Abstract
Considerable effort has been applied towards understanding the precise shaping mechanisms responsible for the diverse range of morphologies exhibited by planetary nebulae (PNe). At least 10-20% of PNe have central stars (CSPN) with a close binary companion thought responsible for heavily shaping the ejected PN during common-envelope (CE) evolution, however morphological studies of the few available examples found no clear distinction between PNe and post-CE PNe. The discovery of several new binary central stars (CSPN) from the OGLE-III photometric variability survey has significantly increased the number of post-CE PNe available for morphological analysis to 30 PNe. High quality Gemini South narrow-band images are presented for most of the OGLE sample, while some previously known post-CE PNe are reanalysed with images from the literature. Nearly 30% of nebulae have canonical bipolar morphologies, however this could be as high as 60% once inclination effects are incorporated with the aid of geometric models. This is the strongest observational evidence yet linking CE evolution to bipolar morphologies. A higher than average proportion of the sample shows low-ionisation knots, filaments or jets suggesting they have a binary origin. These features are also common in nebulae around emission-line nuclei which may be explained by speculative binary formation scenarios for H-deficient CSPN.
Original language | English |
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Pages (from-to) | 249-263 |
Number of pages | 15 |
Journal | Astronomy and Astrophysics |
Volume | 505 |
Issue number | 1 |
DOIs | |
Publication status | Published - 1 Oct 2009 |
Bibliographical note
Copyright 2009 ESO. First published in Astronomy and astrophysics, Vol. 505, No. 1, 2009, published by EDP Sciences. The original publication is available at http://dx.doi.org/10.1051/0004-6361/200912176.Keywords
- ISM: planetary nebulae: general
- Stars: binaries: close