NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Multifrequency light curves of low-frequency variable radio sourcesLight curves for the low-frequency variable sources AO 0235 + 16, NRAO 140, PKS 1117 + 14, DA 406, CTA 102, and 3C 454.3, obtained in monthly observations at 318, 430, and 606 MHz using the 305-m telescope at Arecibo and in bimonthly observations at 880 MHz and 1.4 GHz using the 91-m Green Bank transit telescope during 1980-1983, are presented and analyzed. AO 0235 + 16 is found to have basically canonical variability which is attributed to relativistically moving evolving synchrotron components; but in the other sources, strong simultaneous variations at 318, 430, and 606 MHz are observed to be greatly diminished in amplitude at 880 MHz and 1.4 GHz, confirming the existence of the intermediate-frequency gap at about 1 GHz proposed by Spangler and Cotton (1981). The possibility that a second variability mechanism is active in these sources is explored.
Document ID
19850036079
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Altschuler, D. R.
(Universidad de Puerto Rico Rio Piedras, PR, United States)
Broderick, J. J.
(Puerto Rico Univ. Rio Piedras., United States)
Dennison, B.
(Puerto Rico Univ. Rio Piedras., United States)
Mitchell, K. J.
(Puerto Rico Univ. Rio Piedras., United States)
Odell, S. L.
(Virginia Polytechnic Institute and State University Blacksburg, VA, United States)
Condon, J. J.
(National Radio Astronomy Observatory Charlottesville, VA, United States)
Payne, H. E.
(National Radio Astronomy Observatory Green Bank, WV, United States)
Date Acquired
August 12, 2013
Publication Date
December 1, 1984
Publication Information
Publication: Astronomical Journal
Volume: 89
ISSN: 0004-6256
Subject Category
Astronomy
Accession Number
85A18230
Funding Number(s)
CONTRACT_GRANT: NAG8-348
CONTRACT_GRANT: NSF AST-81-17864
CONTRACT_GRANT: NSF AST-80-18384
CONTRACT_GRANT: NSF AST-79-25345
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available