Optical Identification of Quasar 0917+7122 in the Direction of an Extreme-Ultraviolet Source

Dan Maoz; Eran Ofek; Amotz Shemi; Aaron Barth; Alexei Filippenko; Michael Brotherton; Beverley Wills; Derek Wills; Felix J. Lockman

arXiv · astro-ph/9509120

Optical Identification of Quasar 0917+7122 in the Direction of an Extreme-Ultraviolet Source

Dan Maoz·Eran Ofek·Amotz Shemi·Aaron Barth·Alexei Filippenko·Michael Brotherton·Beverley Wills·Derek Wills·Felix J. Lockman

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Abstract

We report the optical identification of an $R=18.3$ mag, $z=2.432$ quasar at the position of a 6 cm radio source and a faint \rosat PSPC X-ray source. The quasar lies within the error circles of unidentified extreme-UV (EUV) detections by the \euve and \rosat WFC all-sky surveys at $\sim 400$ Å and $\sim 150$ Å, respectively. A 21 cm H I emission measurement in the direction of the quasar with a $21'$-diameter beam yields a total H I column density of $N_{H}=3.3\times 10^{20}$ cm$^{-2}$, two orders of magnitude higher than the maximum allowed for transparency through the Galaxy in the EUV. The source of the EUV flux is therefore probably nearby ($\ltorder 100$ pc), and unrelated to the quasar.

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BibTeX RIS

Dan Maoz, Eran Ofek, Amotz Shemi, Aaron Barth, Alexei Filippenko, Michael Brotherton, Beverley Wills, Derek Wills, Felix J. Lockman. 1995-09-21. Optical Identification of Quasar 0917+7122 in the Direction of an Extreme-Ultraviolet Source. https://arxiv.org/abs/astro-ph/9509120

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