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Surface density of quasars in two high-latitude fieldsFourty-four objects selected for ultraviolet excess have been identified spectroscopically. The objects lie in two Palomar 1.2 m Schmidt fields in the north galactic polar cap, one of 7.7 sq deg centered on Kapteyn Selected Area 29, the other of 36 sq deg centered on SA 55. The objects are characterized by Color Classes (CC) 1A, 1, 1B, 1C, 2, and 3. Quasars comprise 75 percent of the CC 1A objects and 44 percent of the objects in the SA 29 field. Twelve quasars in the SA 29 field comprise a complete sample to B = 18.5 mag, and given an uncorrected surface density of 1.6 quasars/sq deg. This value is essentially that derived by Sandage (1969). Corrections are applied to account for the lack of high redshift quasars. An empirical correction is derived to account for lack of simultaneity in selection and photometry. A corrected lower limit to the surface density is estimated to be 1.85 quasars/sq deg to B = 18.5 mag.
Document ID
19850031178
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Usher, P. D.
(Pennsylvania State University University Park, PA, United States)
Green, R. F.
(Steward Observatory Tucson, AZ, United States)
Huang, K. L.
(Nanjing University Nanjing, People's Republic of China; Pennsylvania State University, University Park, PA, United States)
Warnock, A., III
(NASA Goddard Space Flight Center Laboratory for Astronomy and Solar Physics, Greenbelt, MD, United States)
Date Acquired
August 12, 2013
Publication Date
January 1, 1983
Subject Category
Astronomy
Meeting Information
Meeting: Quasars and gravitational lenses
Location: Cointe-Ougree
Country: Belgium
Start Date: June 21, 1983
End Date: June 24, 1983
Accession Number
85A13329
Funding Number(s)
CONTRACT_GRANT: NSF AST-81-09025
Distribution Limits
Public
Copyright
Other

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