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Gas Dynamic Stripping and X-Ray Emission of Cluster Elliptical Galaxies

Thomas Toniazzo·Sabine Schindler
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Abstract

Detailed 3-D numerical simulations of an elliptical galaxy orbiting in a gas-rich cluster of galaxies indicate that gas dynamic stripping is less efficient than the results from previous, simpler calculations (Takeda et al. 1984; Gaetz et al. 1987) implied. This result is consistent with X-ray data for cluster elliptical galaxies. Hydrodynamic torques and direct accretion of orbital angular momentum can result in the formation of a cold gaseous disk, even in a non-rotating galaxy. The gas lost by cluster galaxies via the process of gas dynamic stripping tends to produce a colder, chemically enriched cluster gas core. A comparison of the models with the available X-ray data of cluster galaxies shows that the X-ray luminosity distribution of cluster galaxies may reflect hydrodynamic stripping, but also that a purely hydrodynamic treatment is inadequate for the cooler interstellar medium near the centre of the galaxy.

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Thomas Toniazzo, Sabine Schindler. 2001-02-12. Gas Dynamic Stripping and X-Ray Emission of Cluster Elliptical Galaxies. https://doi.org/10.1046/j.1365-8711.2001.04385.x

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