Speaker
Description
Magnetic field strength and geometry are fundamental properties which control the formation and evolution of relativistic jets, and their observed emission via the field's impact on particle acceleration. At centimeter-band, where the emission is well-known to be produced by the synchrotron process, magnetic field properties can be constrained using a wealth of data from both single-dish linear polarization measurements exhibiting time-resolved outbursts in light curves, and VLBA imaging data revealing the spatial distribution of this emission. I describe the 3-frequency, source-integrated linear polarization monitoring observations from the University of Michigan program (UMRAO), extending over 40 years for some sources, and MOJAVE VLBA polarimetry imaging results at 15 GHz obtained since 2002. I present recent results on the spatial distribution of the polarization and illustrate how the combined UMRAO and MOJAVE position angle data have been used to probe magnetic field geometry. An emerging picture for the parsec-scale jet includes shocks, a turbulent underlying quiescent jet, and an ordered helical magnetic field component.
