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Chandra Observations of the Evolving Core of the Starburst Galaxy NGC 253

Kimberly Weaver·Timothy Heckman·David Strickland·Michael Dahlem
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Abstract

Chandra observations of the core of the nearby starburst galaxy NGC 253 reveal a heavily absorbed source of hard X-rays embedded within the nuclear starburst region. The source has an unabsorbed, 2 to 10 keV luminosity of >=10^39 erg/s and photoionizes the surrounding gas. We observe this source through a dusty torus with a neutral absorbing column density of NH ~ 2x10^23 cm^-2. The torus is hundreds of pc across and collimates the starburst-driven nuclear outflow. We suggest that the ionizing source is an intermediate-mass black hole or a weakly accreting supermassive black hole, which may signal the beginnings or endings of AGN activity.

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Kimberly Weaver, Timothy Heckman, David Strickland, Michael Dahlem. 2002-07-19. Chandra Observations of the Evolving Core of the Starburst Galaxy NGC 253. https://doi.org/10.1086/342977

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