arXiv 0807.00282008-07astro-ph

An occultation event in a triple post-AGB star

M. Hajduk, A. A. Zijlstra, K. Gesicki

备注：: 4 pages, 5 figures
发表信息：: Astronomy and Astrophysics (2008) 490L 7H
DOI：: 10.1051/0004-6361:200810492

英文摘要：

We study the post-AGB central star of the (bipolar) Galactic bulge planetary nebula M 2-29. We have obtained additional HST imaging and SAAO spectroscopy of the object. The star showed a pronounced, long-lasting occultation with subsequent recovery. The event lasted for almost 3 years, with a secondary minimum 9 years later. The photometric behaviour of M 2-29 resembles the dust-occultation events seen in NGC 2346, and is modeled as an occultation by a circumbinary disk, where the binary period is 18 yr. Modulation during the decline shows evidence for another companion with a period of 23 days.

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