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Date and Time of the Query: 2019-06-24 T08:31:05 PDT
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For refcode 2001ApJS..136..265L:
Retrieve 148 NED objects in this reference.
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NED Abstract

Copyright by American Astronomical Society. Reproduced by permission
2001ApJS..136..265L Dual-Frequency, Multiyear Monitoring Program of Compact Radio Sources T. Joseph W. Lazio and E. B. Waltman Code 7213, Remote Sensing Division, Naval Research Laboratory, Washington, DC 20375-5351; lazio@rsd.nrl.navy.mil, ewaltman@rsd.nrl.navy.mil F. D. Ghigo National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944; fghigo@nrao.edu R. L. Fiedler Code 7260, Remote Sensing Division, Naval Research Laboratory, Washington, DC 20375-5351; fiedler@sealab.nrl.navy.mil R. S. Foster Code 7213, Remote Sensing Division, Naval Research Laboratory, Washington, DC 20375-5351 and K. J. Johnston US Naval Observatory, 3450 Massachusetts Avenue NW, Washington, DC 20392-5420; ken@spica.usno.navy.mil Received 2000 September 6; accepted 2001 May 24 ABSTRACT We present light curves for 149 sources monitored with the Green Bank Interferometer. The light curves are at two radio frequencies (approximately 2.5 and 8.2 GHz) and range from 3 to 15 yr in length, covering the interval 1979-1996, and have a typical sampling of one flux density measurement every 2 days. We have used these light curves to conduct various variability analysis (rms flux density variations and autoregressive, integrated, moving average modeling) of these sources. We find suggestive though not unambiguous evidence that these sources have a common, broadband mechanism for intrinsic variations, in agreement with previous studies of a subset of these sources. We also find that the sources generally display a short-term variability (~10 days) that arises from radio-wave scattering in an extended medium. These conclusions extend those of Fiedler et al., who used a subsample of these data. The primary motivation for this monitoring program was the identification of extreme scattering events (ESEs). In an effort to identify ESEs in a systematic manner, we have taken the wavelet transform of the light curves. We find 15 events in the light curves of 12 sources that we classify as probable ESEs. However, we also find that five ESEs previously identified from these data do not survive our wavelet selection criteria. Future identification of ESEs will probably continue to rely on both visual and systematic methods. Instructions for obtaining the data are also presented. Subject headings: radio continuum: general - scattering - surveys
Retrieve 148 NED objects in this reference.
Please click here for ADS abstract

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