Extragalactic jets from every angle Proceedings IAU Symposium No. 313, 2014 F. Massaro, C. C. Cheung, E. Lopez, A. Siemiginowska, eds. c  International Astronomical Union 2015 doi:10.1017/S1743921315002124 Systematics of jets using multi-wavelength data Prajval Shastri 1,2 , Estrella Jimenez Gomez 1 , Maitrayee Gupta 1 and Grzegorz Madejski 2 1 Indian Institute of Astrophysics, Sarjapur Road, Bangalore 560034, India email: prajval.shastri@gmail.com 2 Kavli Institute of Particle Astrophysics & Cosmology, Stanford University, Palo Alto CA USA Abstract. We investigate the systematics of the properties of highly relativistic jets at multiple frequencies, including F ermi and MOJAVE data. We test the hypothesis that the blazar divide constitutes a dichotomy. We also explore possible measures of the Doppler factor for these highly Doppler-beamed active galactic nuclei. Keywords. galaxies :active, galaxies: jets 1. Introduction Most if not all accreting supermassive black holes appear to produce bipolar outflows of hot gas and bipolar synchrotron-emitting plasma jets. In most active galactic nuclei (AGN) these jets appear quenched well within their host galaxies, and they are referred to as ”radio-quiet” AGN in the literature. Their jets appear not to be significantly rela- tivistic (e.g., Lal et al. 2011; Middelberg et al. 2004) except in the case of the Narrow-Line Seyfert 1 type AGN (e.g., J. Richards, these proceedings). In a small minority (15-20%) of the AGN, however, the jets appear to be launched with large kinetic power and at bulk relativistic speeds, and these jets reach scales of several hundred kiloparsecs and even a megaparsec. AGN with such jets are referred to as ”radio-loud”. It has been well-established that when such jets are oriented close to our line of sight, relativistic aberration strongly affects their observed parameters (e.g., Blandford & Konigl 1979) and their emission is heavily Doppler beamed. These beamed jets dominate surveys at gamma-ray energies (e.g., Ackermann et al. 2011), and have also been the primary candi- dates for the measurement of the apparent proper motion of the jet components via Very Long Baseline Interferometry (e.g., the MOJAVE project: Lister et al. 2009). We present here some work in progress that investigates the systematics of highly relativistically beamed jets, primarily using F ermi and MOJAVE data. 2. The blazar divide Blazars are AGN that exhibit large variability and polarization of their contnuum emission at virtually all wavelengths observed. These characteristics are widely recognised as being hallmarks of relativistic beaming of the large kinetic power jets when the jets are close to the line-of-sight. Several quasars, which, by definition, have prominent broad emission lines in their optical and IR spectra, show blazar characterisitcs and being quasars, their radio structures are of the Fanaroff-Riley II type. There are also AGN which exhibit blazar characteristics, but have only weak or no emission lines in their optical spectra. Referred to as BL Lacertids or BL Lacs in the literature, they are believed to have the synchrotron component overwhelmingly dominate the emission at all wavelengths 164 https://www.cambridge.org/core/terms. https://doi.org/10.1017/S1743921315002124 Downloaded from https://www.cambridge.org/core. IP address: 3.92.57.205, on 25 May 2020 at 20:50:36, subject to the Cambridge Core terms of use, available at