Dynamical friction-driven orbital circularization in rotating discs: a semi-analytical description. Issue 2 (15th April 2020)

• Record Type: Journal Article
• Authors: Bonetti, Matteo; Bortolas, Elisa; Lupi, Alessandro; Dotti, Massimo; Raimundo, Sandra I
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 494:Issue 2(2020)
• Page Start: 3053
• Page End: 3059
• Publication Date: 2020-04-15
• Subjects: gravitation -- methods: numerical -- stars: kinematics and dynamics -- galaxies: nuclei -- galaxies: structure; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/staa964
• Languages: English
• ISSNs: 0035-8711

Abstract

ABSTRACT: We present and validate a novel semi-analytical approach to study the effect of dynamical friction (DF) on the orbits of massive perturbers in rotating stellar discs. We find that DF efficiently circularizes the orbit of co-rotating perturbers, while it constantly increases the eccentricity of counter-rotating ones until their angular momenta reverse, then once again promoting circularization. Such 'drag toward circular co-rotation' could shape the distribution of orientations of kinematically decoupled cores in disc galaxies, naturally leading to the observed larger fraction of co-rotating cores.