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Interstellar medium disruption in the Centaurus A group

A. Bouchard·H. Jerjen·G. S. Da Costa·J. Ott
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Abstract

We present the results of a 21 cm neutral hydrogen (HI) line detection experiment in the direction of 18 low luminosity dwarf galaxies of the Centaurus A group, using the Australia Telescope National Facility 64m Parkes Radio Telescope and the Australia Telescope Compact Array. Five dwarfs have HI masses between M_HI=4x10^5 to M_HI=2.1x10^7 Msol and 0.04 10^7 Msol or M_HI<10^6 Msol. This gap may be explained by the ram pressure stripping mechanism at work in this dense environment where all galaxies with M_HI<10^7 Msol have been stripped of their gas. The required intergalactic medium density to achieve this is ~10^-3 cm^-3.

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A. Bouchard, H. Jerjen, G. S. Da Costa, J. Ott. 2006-11-14. Interstellar medium disruption in the Centaurus A group. https://doi.org/10.1086/509132

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