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arXiv · 1805.03429

Discovery of two bright $z\sim5$ quasars with SkyMapper, Pan-STARRS1 and WISE

Zefeng Li·Christian Wolf·Fuyan Bian·Christopher A. Onken·Brian P. Schmidt·Patrick Tisserand·Noura Alonzi·Wei Jeat Hon
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Abstract

We present a search for bright $z\sim5$ quasars using imaging data from SkyMapper Southern Survey, Pan-STARRS1 and the Wide-field Infrared Survey Explorer (WISE). We select two sets of candidates using WISE with optical bands from SkyMapper and alternatively from Pan-STARRS1, limited to a magnitude of $i<18.2$. We follow up several candidates with spectroscopy and find that the four candidates common to both lists are quasars, while others turned out to be cool stars. Two of the four quasars, SMSS J013539.27-212628.4 at $z=4.86$ and SMSS J093032.58-221207.7 at $z=4.94$, are new discoveries and ranked among the dozen brightest known $z>4.5$ QSOs in the $i$-band.

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Zefeng Li, Christian Wolf, Fuyan Bian, Christopher A. Onken, Brian P. Schmidt, Patrick Tisserand, Noura Alonzi, Wei Jeat Hon. 2018-05-09. Discovery of two bright $z\sim5$ quasars with SkyMapper, Pan-STARRS1 and WISE. https://arxiv.org/abs/1805.03429

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