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Reddening-Independent Quasar Selection from a Wide-Field Optical and Near-IR Imaging Survey

R. G. Sharp·C. N. Sabbey·A. K. Vivas·A. Oemler Jr·R. G. McMahon·S. T. Hodgkin·P. S. Coppi
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Abstract

We combine deep, wide-field near-IR and optical imaging to demonstrate a reddening-independent quasar selection technique based on identifying outliers in the (g-z) / (z-H) colour diagram. In three fields covering a total of ~0.7 deg^2 to a depth of m_H~18, we identified 68 quasar candidates. Follow-up spectroscopy for 32 objects from this candidate list confirmed 22 quasars (0.86 65% success rate), a high surface density of candidates, and is relatively independent of reddening. We discuss the implications for star/galaxy separation for IR based surveys for quasars. We provide the coordinate list and follow-up spectroscopy for the sample of 22 confirmed quasars.

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R. G. Sharp, C. N. Sabbey, A. K. Vivas, A. Oemler Jr, R. G. McMahon, S. T. Hodgkin, P. S. Coppi. 2002-09-19. Reddening-Independent Quasar Selection from a Wide-Field Optical and Near-IR Imaging Survey. https://doi.org/10.1046/j.1365-8711.2002.05961.x

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