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arXiv · 1308.0728

X-ray discovery of a dwarf-galaxy galaxy collision

Gordon P. Garmire
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Abstract

We report the discovery of a probable dwarf galaxy colliding with NGC 1232. This collision is visible only in the X-ray spectral band, and it is creating a region of shocked gas with a temperature of 5.8 MK covering an impact area 7.25 kpc in diameter. The X-ray luminosity is 3.7 x1038ergs s-1. The long lifetime of this gas against radiative and adiabatic cooling should permit the use of the luminous afterglow from such collisions to be used as a way of estimating their importance in galaxy evolution.

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Gordon P. Garmire. 2013-08-03. X-ray discovery of a dwarf-galaxy galaxy collision. https://doi.org/10.1088/0004-637x/770/1/17

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