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arXiv · astro-ph/9812280

Spectroscopy of Quasar Candidates from SDSS Commissioning Data

Xiaohui Fan·Michael A. Strauss·James Annis·James E. Gunn·Gregory S. Hennessy·Zeljko Ivezic·Gillian R. Knapp·Robert H. Lupton·Jeffrey A. Munn·Heidi J. Newberg·Donald P. Schneider·Brian Yanny
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Abstract

The Sloan Digital Sky Survey has obtained images in five broad-band colors for several hundred square degrees. We present color-color diagrams for stellar objects, and demonstrate that quasars are easily distinguished from stars by their distinctive colors. Follow-up spectroscopy in less than ten nights of telescope time has yielded 22 new quasars, 9 of them at $z> 3.65$, and one with $z = 4.75$, the second highest-redshift quasar yet known. Roughly 80% of the high-redshift quasar candidates selected by color indeed turn out to be high-redshift quasars.

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Xiaohui Fan, Michael A. Strauss, James Annis, James E. Gunn, Gregory S. Hennessy, Zeljko Ivezic, Gillian R. Knapp, Robert H. Lupton, Jeffrey A. Munn, Heidi J. Newberg, Donald P. Schneider, Brian Yanny. 1998-12-15. Spectroscopy of Quasar Candidates from SDSS Commissioning Data. https://doi.org/10.1063/1.58612

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