EDP Sciences
Free access
Volume 444, Number 2, December III 2005
Page(s) 455 - 459
Section Extragalactic astronomy
DOI http://dx.doi.org/10.1051/0004-6361:20052894

A&A 444, 455-459 (2005)
DOI: 10.1051/0004-6361:20052894

Interaction between a galactic disk and a live dark halo with an anisotropic velocity distribution

B. Fuchs1 and E. Athanassoula2

1  Astronomisches Rechen-Institut, Mönchhofstrasse 12-14, 69120 Heidelberg, Germany
    e-mail: fuchs@ari.uni-heidelberg.de
2  Observatoire de Marseille, 2 Place Le Verrier, 13248 Marseille Cedex 04, France

(Received 17 February 2005 / Accepted 21 September 2005)

We have extended previous analytical studies of the interaction of dark halos with galactic disks by introducing for the halo particles anisotropic distribution functions in phase space. For this purpose we have employed the shearing sheet model of a patch of a galactic disk embedded in a homogeneous halo. We find that velocity anisotropy increases considerably the maximum growth factor of perturbations in the disk.

Key words: galaxies: kinematics and dynamics -- galaxies: spiral

© ESO 2005