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

摘要

Simultaneous and near-simultaneous optical, infrared, and radio observations were made to search for intraday (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)