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Cited by 1,003

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Spectroscopic Target Selection in the Sloan Digital Sky Survey: The Quasar Sample

Open access
Richards, Gordon T., Fan, Xiaohui, Newberg, Heidi Jo, Strauss, Michael A., Vanden Berk, Daniel E., Schneider, Donald P., Yanny, Brian, Boucher, Adam, Burles, Scott, Frieman, Joshua A., Gunn, James E., Hall, Patrick B., Ivezić, Željko, Kent, Stephen, Loveday, Jon, Lupton, Robert H., Rockosi, Constance M., Schlegel, David J., Stoughton, Chris, SubbaRao, Mark, York, Donald G.·2002·The Astronomical Journal

Abstract

We describe the algorithm for selecting quasar candidates for optical spectroscopy in the Sloan Digital Sky Survey. Quasar candidates are selected via their non-stellar colors in "ugriz" broad-band photometry, and by matching unresolved sources to the FIRST radio catalogs. The automated algorithm is sensitive to quasars at all redshifts lower than z=5.8. Extended sources are also targeted as low-redshift quasar candidates in order to investigate the evolution of Active Galactic Nuclei (AGN) at the faint end of the luminosity function. Nearly 95% of previously known quasars are recovered (based on 1540 quasars in 446 square degrees). The overall completeness, estimated from simulated quasars, is expected to be over 90%, whereas the overall efficiency (quasars:quasar candidates) is better than 65%. The selection algorithm targets ultraviolet excess quasars to i^*=19.1 and higher-redshift (z>3) quasars to i^*=20.2, yielding approximately 18 candidates per square degree. In addition to selecting ``normal'' quasars, the design of the algorithm makes it sensitive to atypical AGN such as Broad Absorption Line quasars and heavily reddened quasars.

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Metadata

Authors
Richards, G. T., Fan, X., Newberg, H. J., Strauss, M. A., Vanden Berk, D. E., Schneider, D. P., Yanny, B., Boucher, A., Burles, S., Frieman, J. A., Gunn, J. E., Hall, P. B., Ivezić, Ž., Kent, S., Loveday, J., Lupton, R. H., Rockosi, C. M., Schlegel, D. J., Stoughton, C., SubbaRao, M., & York, D. G.
Venue
The Astronomical Journal
Published
2002-06
Volume
123
Issue
6
Pages
2945-2975
ISSN
  • 0004-6256 (ISSN-L)
  • 1538-3881
OpenAlex
W2037502800
Cited by
1,003
References
3
FWCI
34.91
Type
journal article
Language
en
Open access
green

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CoChat. (2026). Citation check: Spectroscopic Target Selection in the Sloan Digital Sky Survey: The Quasar Sample. https://app.cochat.ai/papers/10.1086/340187
The paper
Richards, G. T., Fan, X., Newberg, H. J., Strauss, M. A., Vanden Berk, D. E., Schneider, D. P., Yanny, B., Boucher, A., Burles, S., Frieman, J. A., Gunn, J. E., Hall, P. B., Ivezić, Ž., Kent, S., Loveday, J., Lupton, R. H., Rockosi, C. M., Schlegel, D. J., Stoughton, C., . . . York, D. G. (2002). Spectroscopic Target Selection in the Sloan Digital Sky Survey: The Quasar Sample. The Astronomical Journal. https://doi.org/10.1086/340187

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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.