The super-NFW model: An analytic dynamical model for cold dark matter haloes and elliptical galaxies


Type
Article
Change log
Authors
Lilley, EJ 
Evans, NW 
Sanders, JL 
Abstract

An analytic galaxy model with ρr−1 at small radii and ρr−3.5 at large radii is presented. The asymptotic density fall-off is slower than the Hernquist model, but faster than the Navarro-Frenk-White (NFW) profile for dark matter haloes, and so in accord with recent evidence from cosmological simulations. The model provides the zeroth-order term in a biorthornomal basis function expansion, meaning that axisymmetric, triaxial and lopsided distortions can easily be added (much like the Hernquist model itself which is the zeroth-order term of the Hernquist-Ostriker expansion). The properties of the spherical model, including analytic distribution functions which are either isotropic, radially anisotropic or tangentially anisotropic, are discussed in some detail. The analogue of the mass-concentration relation for cosmological haloes is provided.

Description
Keywords
galaxies: haloes, galaxies: kinematics and dynamics, dark matter
Journal Title
Monthly Notices of the Royal Astronomical Society
Conference Name
Journal ISSN
0035-8711
1365-2966
Volume Title
476
Publisher
Oxford University Press (OUP)
Sponsorship
Science and Technology Facilities Council (ST/N000927/1)
Science and Technology Facilities Council (1788901)
EJL and JLS acknowledge financial support from the Science and Technology Facilities Council.