Wednesday 24 November at 3:30pm

Alan Marscher & Svetlana Marchenko - Boston University

"Multiwavelength Polarization Observations of Jets in Blazars"

ABSTRACT: "We are engaged in a long-term project (with a number of collaborators, including Walter Gear and Jason Stevens) to monitor the polarized intensity structure of 15 blazars and blazar-like radio galaxies with the VLBA at 43 GHz and with the JCMT at 230 GHz. We will report on the first phase of this project. In a number of cases, the 230 GHz polarization matches closely that of the 43 GHz core region, although usually with a higher fractional polarization (indicating more localized emission regions), while for others the relationship is not as clear (suggesting physically distinct emission regions). The polarization near the core changes on timescales shorter than our monitoring interval of two months in some of the sources. The cores of the two radio galaxies are not polarized at 43 GHz, but appear to be at 230 GHz, which suggests that Faraday depolarization occurs at the lower frequency. The core of 3C 273 appears not to be significantly polarized at both frequencies. "The talk will include movies that show the evolution of the polarized intensity VLBA images alongside the variability of the 230 GHz integrated polarization."