Density waves in the shearing sheet IV. Interaction with a live dark halo

Abstract

It is shown that if the self-gravitating shearing sheet, a model of a patch of a galactic disk, is embedded in a live dark halo, this has a strong effect on the dynamics of density waves in the sheet. I describe how the density waves and the halo interact via halo particles either on orbits in resonance with the wave or on non-resonant orbits. Contrary to expectation the presence of the halo leads to a very considerable enhancement of the amplitudes of the density waves in the shearing sheet. This effect appears to be the equivalent of the recently reported enhanced growth of bars in numerically simulated stellar disks embedded in live dark halos. Finally I discuss the transfer of linear momentum from a density wave in the sheet to the halo and show that it is mediated only by halo particles on resonant orbits.

arXiv comment8 pages, 4 figures, accepted by Astron. Astrophys

References in corpus (8)

• What determines the strength and the slowdown rate of bars ?
• Constraints from Dynamical Friction on the Dark Matter Content of Barred Galaxies
• Bar-Halo Interaction and Bar Growth
• Bar-driven dark halo evolution: a resolution of the cusp--core controversy
• Bars and Dark Matter Halo Cores
• Density waves in the shearing sheet I. Swing amplification
• Dynamical stability and evolution of the discs of Sc galaxies
• Constraints on the Decomposition of the Rotation Curves of Spiral Galaxies

Cited by in corpus (10)

• Lopsided Spiral Galaxies
• A bar in the inner halo of barred galaxies I. Structure and kinematics of a representative model
• Dynamical Evolution of Barred Galaxies
• Galactic disc profiles and a universal angular momentum distribution from statistical physics
• Density waves in the shearing sheet V. Feedback cycle for swing amplification by non-linear effects
• Interaction between a galactic disk and a live dark halo with an anisotropic velocity distribution
• Dynamical friction force exerted on spherical bodies
• Dark matter spiral arms in Milky Way-like halos
• Jeans instability of a galactic disk embedded in a live dark halo
• Bars, Spiral Structure, and Secular Evolution in Disk Galaxies