Bending instabilities at the origin of persistent warps: a new constraint on dark matter halos

Abstract

A substantial fraction of the warps in spiral galaxies may result from bending instabilities if the disks are essentially self-gravitating. With N-body simulations, we show that galaxies with self-gravitating disks as thick as HI disks are subject to bending instabilities generating S-shaped, U-shaped or asymmetric warps. S-shaped warps persist during several rotations and keep the line of node straight. The warp amplitudes generated by bending instabilities remain however modest. Other factors must be invoked for extreme warped disks. However, bending instabilities can account for most of the cases reported in optical surveys, where the warp angle is generally less than $5^{\circ }$. This mode of warping is very sensitive to the disk flattening. It also constrains the fraction of dark matter distributed in the disk and in the dark halo.

arXiv comment11 pages. Accepted for publication on A&A Main Journal. Paper with full resolution images is available at : http://obswww.unige.ch/~revaz/bending/bending.pdf http://obswww.unige.ch/~revaz/bending/bending.ps.gz

References in corpus (16)

• Properties of galaxy dark matter halos from weak lensing
• Gas Dynamics in the Milky Way: Second Pattern Speed and Large-Scale Morphology
• The Disk and Dark Halo Mass of the Barred Galaxy NGC 4123. II. Fluid-Dynamical Models
• Warps and Cosmic Infall
• The Damping and Excitation of Galactic Warps by Dynamical Friction
• On the apparent coupling of neutral hydrogen and dark matter in spiral galaxies
• Generation of galactic disc warps due to intergalactic accretion flows onto the disc
• The Shape and Figure Rotation of NGC 2915's Dark Halo
• Gas, Dust, and Young Stars in the Outer Disk of M 31
• A catalog of warps in spiral and lenticular galaxies in the Southern hemisphere
• The Settling of Warped Disks in Oblate Dark Halos
• Axisymmetric bending oscillations of stellar disks
• On the Spiral Structure of NGC 2915 and Dark Matter
• A New Probe of the Molecular Gas in Galaxies: Application to M101
• Spiral galaxies with large optical warps
• Massive Disks in Low Surface Brightness Galaxies

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