1999/03/31 by Mario G. Abadi, Ben Moore, Richard G. Bower · 1 citation
Physics and Astronomy · #astro-ph
paper · pdf · doi:10.1046/j.1365-8711.1999.02715.x
published as Mon.Not.Roy.Astron.Soc.308:947-954,1999 · 8 pages, 7 figures, to be published in MNRAS. Levels added/corrected on figures 3, 4 and 5
arxiv created 1999/03/31 · arxiv updated 2009/12/01
We use 3-dimensional SPH/N-BODY simulations to study ram pressure stripping of gas from spiral galaxies orbiting in clusters. We find that the analytic expectation of Gunn & Gott (1972) relating the gravitational restoring force provided by the disk to the ram pressure force, provides a good approximation to the radius that gas will be stripped from a galaxy. However, at small radii it is also important to consider the potential provided by the bulge component. A spiral galaxy passing through the core of a rich cluster such as Coma, will have its gaseous disk truncated to ∼ 4 kpc, thus losing ∼ 80% of its diffuse gas mass. The timescale for this to occur is a fraction of a crossing time ∼ 107 years. Galaxies orbiting within poorer clusters, or inclined to the direction of motion through the intra-cluster medium will lose significantly less gas. We conclude that ram-pressure alone is insufficient to account for the rapid and widespread truncation of star-formation observed in cluster galaxies, or the morphological transformation of Sab's to S0's that is necessary to explain the Butcher-Oemler effect.