Eccentricity-pumping in post-AGB stars with circumbinary discs

¹ Argelander-institut für Astronomie, University of Bonn, Auf dem Hügel 71, 53121 Bonn, Germany
e-mail: tdermine@gmail.com
² Institut d’Astronomie et d’Astrophysique, Université Libre de Bruxelles, Belgium
³ Instituut voor Sterrenkunde, K.U. Leuven, Belgium

Received: 17 April 2012
Accepted: 7 December 2012

Abstract

Circumbinary discs are commonly observed around post-asymptotic giant branch (post-AGB) systems and are known to play an important role in their evolution. Several studies have pointed out that a circumbinary disc interacts through resonances with the central binary and leads to angular momentum transfer from the central binary orbit to the disc. This interaction may be responsible for a substantial increase in the binary eccentricity. We investigate whether this disc eccentricity-pumping mechanism can be responsible for the high eccentricities commonly found in post-AGB binary systems.