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No evidence for radio-quiet BL Lacertae objectsUsing a large, flux-limited sample of faint X-ray sources, a search has been conducted for radio-quiet BL Lacertae objects. None has been found. Thirty-two X-ray-selected BL Lac objects and BL Lac candidates have been found within the sources of the Einstein Medium Sensitivity Survey (EMSS). Thirty-one of these have been observed with the VLA and all have been detected at 5 GHz. While the optical magnitudes of the EMSS BL Lac objects range from 17 to 20.8, their radio-to-optical spectral indices occupy a very small range. The very bright X-ray-selected BL Lac objects like PKS 2155-304 and Markarian 501 have similar range values. Therefore, unlike the clear dichotomy between radio-loud quasars and radio-quiet QSOs, there is no evidence for two populations of Lacertids distinguished by radio loudness.
Document ID
19900033234
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Stocke, John T.
(Colorado, University Boulder, United States)
Morris, Simon L.
(Mount Wilson and Las Campanas Observatories Pasadena, United States)
Gioia, Isabella
(Colorado Univ. Boulder, CO, United States)
Maccacaro, Tommmaso
(Colorado Univ. Boulder, CO, United States)
Schild, R. E.
(Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Date Acquired
August 14, 2013
Publication Date
January 1, 1990
Publication Information
Publication: Astrophysical Journal, Part 1
Volume: 348
ISSN: 0004-637X
Subject Category
Astrophysics
Accession Number
90A20289
Funding Number(s)
CONTRACT_GRANT: NAG8-658
CONTRACT_GRANT: NAS8-30751
CONTRACT_GRANT: NSF AST-87-15893
CONTRACT_GRANT: NAS5-30101
Distribution Limits
Public
Copyright
Other

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