Péridier Library Abstract Archive

Abstract No. UT 365

Title: Variability and Nature of the Binary in the Red Rectangle Nebula
Author(s): C. Waelkens, H. Van Winckel, L.B.F.M. Waters, and E.J. Bakker
Keywords: Stars: binaries: close; Stars: evolution; Stars: individual: HD44179; Stars: AGB and post-AGB; dust, extinction
E-Mail: Eric J. Bakker (to request a full copy of this paper)
Preprint: 9609058 Document source or PostScript
Release date: 09/27/96 14:31:00
Publication status: accepted by A&A letters
Comments: 4 pages, 3 figures

We present new observations of the central binary inside the Red Rectangle nebula. The detection of zinc in the optical spectrum confirms that the peculiar photospheric abundances are due to accretion of circumstellar gas. Grey brightness variations with the orbital period are observed. They are interpreted as being due to the variation of the scattering angle with orbital phase. The small orbital separation of the system is not compatible with previous normal evolution of the primary on the AGB. We point out the similarity of the orbital history of this and other similar systems with those of some close Barium stars and suggest that the non-zero eccentricity of the orbit is the result of tidal interaction with the circumbinary disk.