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Chandra Detection of a Hot Gaseous Corona Around the Edge-on Galaxy NGC 4631

Q. Daniel Wang·Stefan Immler·Rene Walterbos·James T. Lauroesch·Dieter Breitschwerdt
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Abstract

We present a Chandra X-ray observation that shows, unambiguously for the first time, the presence of a giant diffuse X-ray-emitting corona around the edge-on disk galaxy NGC 4631. This corona, with a characteristic thermal temperature of 2-7\times10^6 K, extends as far as 8 kpc away from the galactic plane. The X-ray morphology resembles the radio halo of the galaxy, indicating a close connection between outflows of hot gas, cosmic rays, and magnetic field from the galactic disk. Enhanced diffuse X-ray emission is apparently enclosed by numerous Hα-emitting loops blistered out from the central disk of the galaxy, as is evident in a comparison with our deep Hubble Space Telescope imaging.

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Q. Daniel Wang, Stefan Immler, Rene Walterbos, James T. Lauroesch, Dieter Breitschwerdt. 2001-05-30. Chandra Detection of a Hot Gaseous Corona Around the Edge-on Galaxy NGC 4631. https://doi.org/10.1086/323179

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