NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-04-18 T05:37:50 PDT
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For refcode 2015ApJS..219...39R:
There are 1486864 NED objects in this reference.
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NED Abstract

Copyright by American Astronomical Society. Reproduced by permission
2015ApJS..219...39R Bayesian High-redshift Quasar Classification from Optical and Mid-IR Photometry Richards, Gordon T.; Myers, Adam D.; Peters, Christina M.; Krawczyk, Coleman M.; Chase, Greg; Ross, Nicholas P.; Fan, Xiaohui; Jiang, Linhua; Lacy, Mark; McGreer, Ian D.; Trump, Jonathan R.; Riegel, Ryan N. Abstract. We identify 885,503 type 1 quasar candidates to i<~ 22 using the combination of optical and mid-IR photometry. Optical photometry is taken from the Sloan Digital Sky Survey-III: Baryon Oscillation Spectroscopic Survey (SDSS-III/BOSS), while mid-IR photometry comes from a combination of data from the Wide-field Infrared Survey Explorer (WISE) "AllWISE" data release and several large-area Spitzer Space Telescope fields. Selection is based on a Bayesian kernel density algorithm with a training sample of 157,701 spectroscopically confirmed type 1 quasars with both optical and mid-IR data. Of the quasar candidates, 733,713 lack spectroscopic confirmation (and 305,623 are objects that we have not previously classified as photometric quasar candidates). These candidates include 7874 objects targeted as high-probability potential quasars with 3.5\lt z\lt 5 (of which 6779 are new photometric candidates). Our algorithm is more complete to z\gt 3.5 than the traditional mid-IR selection "wedges" and to 2.2\lt z\lt 3.5 quasars than the SDSS-III/BOSS project. Number counts and luminosity function analysis suggest that the resulting catalog is relatively complete to known quasars and is identifying new high-z quasars at z\gt 3. This catalog paves the way for luminosity-dependent clustering investigations of large numbers of faint, high-redshift quasars and for further machine-learning quasar selection using Spitzer and WISE data combined with other large-area optical imaging surveys. Key words: catalogs, infrared: galaxies, methods: statistical, quasars: general
There are 1486864 NED objects in this reference.
Please click here for ADS abstract

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