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Limits on the X-ray emission from several hyperluminous IRAS galaxies

R. J. Wilman·A. C. Fabian·R. M. Cutri·C. S. Crawford·W. N. Brandt
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Abstract

We report long, pointed ROSAT HRI observations of the hyperluminous galaxies IRAS F00235+1024, F12514+1027, F14481+4454 and F14537+1950. Two of them are optically classified as Seyfert-like. No X-ray sources are detected at the positions of any of the objects, with a mean upper limit L(X)/L(Bol) of 2.3 times 10^-4. This indicates that any active nuclei are either atypically weak at X-ray wavelengths or obscured by column densities N(H)>10^23 cm^-2. They differ markedly from `ordinary' Seyfert 2 galaxies, bearing a closer resemblance in the soft X-ray band to composite Seyfert 2 galaxies or to some types of starburst.

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R. J. Wilman, A. C. Fabian, R. M. Cutri, C. S. Crawford, W. N. Brandt. 1998-08-28. Limits on the X-ray emission from several hyperluminous IRAS galaxies. https://doi.org/10.1046/j.1365-8711.1998.02047.x

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