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The cosmological evolution of BL Lacertae objectsUsing a complete, X-ray selected sample of BL Lacertae Objects (XBLs), we find that V sub e/V sub a = 0.34 +/- 0.06 implying that the cosmological evolution of this type of AGN is 'negative'; i.e., fewer or less luminous BL Lacs in the past compared to the current epoch. In the process of deriving this result, the selection criteria and observational properties of XBLs are described.
Document ID
19930044807
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Stocke, John T. (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Perlman, Eric S. (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Wurtz, Ron (Colorado Univ. Boulder, United States)
Morris, Simon L. (Carnegie Institution of Washington, Observatories, Pasadena CA, United States)
Date Acquired
August 16, 2013
Publication Date
January 1, 1991
Publication Information
Publication: In: The space distribution of quasars; Proceedings of the Workshop, Victoria, Canada, June 3-5, 1991 (A93-28776 10-90)
Publisher: Astronomical Society of the Pacific
Subject Category
Astrophysics
Accession Number
93A28804
Funding Number(s)
CONTRACT_GRANT: NAG5-1584
CONTRACT_GRANT: NSF AST-90-20008
CONTRACT_GRANT: NAG5-1224
Distribution Limits
Public
Copyright
Other

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