On the relationship between jet and broad emission lines variability in Flat Spectrum Radio Quasars
Abstract
Studies of the relationship between variations in the jet continuum emission and those of broad emission lines (and disk emission) can provide new clues about the structure of the central regions of jetted AGNs and properties of the outflow, such as the location of the active region. Thanks to Fermi and the large multiwavelength coverage that it stimulated (and supported) high quality data are now available for several blazars and this type of investigation is becoming possible and beginning to bear fruit. Recent results on 3C 454.3 (e.g. by Isler et al. 2013, Leon-Tavares et al. 2012) and other luminous FSRQ (e.g. PKS 1510-089, Isler et al.) reveal a connection between broad emission lines intensity and variations of the jet's non-thermal continuum. This suggests that the latter may be responsible for the line variability, a rather unexpected possibility, poorly explored, though not totally surprising. These new results and data certainly motivate a closer look at the possible (radiative) interplay between jet, accretion and "ambient gas", which is essential to understand observations and draw from them constraints on the geometry and dynamics of the AGN components, such as the location where the jet becomes dissipative. In particular the interpretation of the correlated (or not) variability requires to look more in depth at the relationship between the various "radiative signals", some of which may be responsible for causing variations in other components, examples being BLR radiation seeding inverse Compton emission in the jet, disk emission increasing BLR power, or jet emission ionizing part of the BLR as recently discussed. Because the jet "blob" itself moves nearly at the same speed of the "signals", the actual relationships among observables are somewhat at odds with the naive intuition. I will present results of our study of the observational implications/appearance of variations originating in different components and discuss the implications for the interpretation of recent novel observational work. GF acknowledges support from NNX11AO15G (Fermi GI), NNX12AE43G (NASA/ADAP)
- Publication:
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American Astronomical Society Meeting Abstracts #223
- Pub Date:
- January 2014
- Bibcode:
- 2014AAS...22321001F