University of Surrey

Test tubes in the lab Research in the ATI Dance Research

Massive black hole binary eccentricity in rotating stellar systems

Sesana, A, Gualandris, A and Dotti, M (2011) Massive black hole binary eccentricity in rotating stellar systems

Full text not available from this repository.


In this letter we study the eccentricity evolution of a massive black hole (MBH) binary (MBHB) embedded in a rotating stellar cusp. Following the observation that stars on counter-rotating (with respect to the MBHB) orbits extract angular momentum from the binary more efficiently then their co-rotating counterparts, the eccentricity evolution of the MBHB must depend on the degree of co-rotation (counter-rotation) of the surrounding stellar distribution. Using an hybrid scheme that couples numerical three-body scatterings to an analytical formalism for the cusp-binary interaction, we verify this hypothesis by evolving the MBHB in spherically symmetric cusps with different fractions F of co-rotating stars. Consistently with previous works, binaries in isotropic cusps (F=0.5) tend to increase their eccentricity, and when F approaches zero (counter-rotating cusps) the eccentricity rapidly increases to almost unity. Conversely, binaries in cusps with a significant degree of co-rotation (F>0.7) tend to become less and less eccentric, circularising quite quickly for F approaching unity. Direct N-body integrations performed to test the theory, corroborate the results of the hybrid scheme, at least at a qualitative level. We discuss quantitative differences, ascribing their origin to the oversimplified nature of the hybrid approach.

Item Type: Article
Divisions : Surrey research (other units)
Authors :
Sesana, A
Dotti, M
Date : 3 May 2011
DOI : 10.1111/j.1745-3933.2011.01073.x
Uncontrolled Keywords : astro-ph.GA, astro-ph.GA
Related URLs :
Depositing User : Symplectic Elements
Date Deposited : 17 May 2017 13:00
Last Modified : 24 Jan 2020 23:15

Actions (login required)

View Item View Item


Downloads per month over past year

Information about this web site

© The University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom.
+44 (0)1483 300800