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AXJ1749+684: a narrow emission-line galaxy with a flat X-ray spectrum

K. Iwasawa·A. C. Fabian·W. N. Brandt·C. S. Crawford·O. Almaini
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Abstract

We report the serendipitous detection of an X-ray source, AXJ1749+684, with the ASCA Gas Imaging Spectrometer. AXJ1749+684 is identified with a LINER/starburst-type spiral galaxy KUG 1750+683A at a redshift z = 0.05. It has a hard X-ray spectrum, consistent with that of the X-ray background (XRB) in the 1-10 keV band. Despite the optical classification, the X-ray luminosity cannot be explained by starburst activity. Combined with spatial variations in the optical emission line ratios, this suggests the presence of an obscured Seyfert nucleus embedded within a starforming galaxy. Similar behaviour could explain the ambiguous properties of the faint narrow-line X-ray galaxies (NLXGs) emerging from deep X-ray surveys.

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K. Iwasawa, A. C. Fabian, W. N. Brandt, C. S. Crawford, O. Almaini. 1997-08-13. AXJ1749+684: a narrow emission-line galaxy with a flat X-ray spectrum. https://doi.org/10.1093/mnras%2F291.1.l17

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