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FIRST-2MASS Sources Below the APM Detection Threshold: A Population of Highly Reddened Quasars

Eilat Glikman·Michael D. Gregg·Mark Lacy·David J. Helfand·Robert H. Becker·Richard L. White
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Abstract

We have constructed a sample of bright near-infrared sources which are detected at radio wavelengths but undetected on the POSS I plates in order to search for a population of dust-obscured quasars. Optical and infrared spectroscopic followup of the sample has led to the discovery of seventeen heavily reddened quasars (B-K>6.5), fourteen of which are reported here for the first time. This has allowed us to define a region in the R-K, J-K color plane in which 50% of the radio-selected objects are highly reddened quasars. We compare the surface density of this previously overlooked population to that of UVX- radio-selected quasars, finding that they make up ~20% of the total quasar population for K < 15.5.

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Eilat Glikman, Michael D. Gregg, Mark Lacy, David J. Helfand, Robert H. Becker, Richard L. White. 2004-02-16. FIRST-2MASS Sources Below the APM Detection Threshold: A Population of Highly Reddened Quasars. https://doi.org/10.1086/383305

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