Accession Number : AD0752214

Title :   3C 120, BL Lac, and OJ 287: Coordinated Optical, Infrared, and Radio Observations of Intraday Variability.

Descriptive Note : Rept. for Nov 71-Aug 72.

Corporate Author : AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS

Report Date : 30 NOV 1972

Pagination or Media Count : 32

Abstract : Simultaneous and near-simultaneous optical, infrared, and radio observations were made to search for intraday (time scale <24h) variability of the radiation from 3C 120, BL Lac, and OJ 287, sources known to be active at both radio and optical wavelengths on time scales of days or longer. Optical interday (time scale >24h) variability was found for all three sources. The finding of optical intraday variability for BL Lac verified earlier results. The 3.5-mm data strongly suggest intraday variations of OJ 287 with amplitudes as large as about 40%. The infrared data for OJ 287 show variability of about 25% on one night but show no correlation with the 3.5-mm data. (Author)

Descriptors :   (*EXTRATERRESTRIAL RADIO WAVES, CORRELATION TECHNIQUES), RADIO ASTRONOMY, OPTICAL PROPERTIES, INFRARED SPECTROSCOPY, MILLIMETER WAVES

Subject Categories : Astrophysics

Distribution Statement : APPROVED FOR PUBLIC RELEASE