[5/12] The Plasma-Physics of AGN on (Sub)Parsec Scales
2017.05.11 12:42
제목 : The Plasma-Physics of AGN on (Sub)Parsec Scales
연사 : Sasacha Trippe 교수님 (서울대학교)
언어 : English
요약
"The Korean VLBI Network (KVN) is capable of simultaneous multi-frequency full polarization observation observations. This makes the KVN ideal for studying the jet physics of radio-bright active galactic nuclei, especially blazars.
Firstly, I present results of a monitoring study of BL Lacertae
from 2013 to 2016. BL Lac's radio core shows an exponential decay of brightness
over time, with the decay time scale depending on frequency. The resulting
scaling law suggests that the (sub-)mm radio core is a standing re-collimation shock.
Secondly,
I present the first systematic study of multi-frequency blazar polarization
with KVN. We have been able to obtain high-quality linear polarization data for
several sources, with typical degrees of polarization being on the order of few
per cent. Faraday rotation measures (RM), which probe particle densities and
magnetic field strengths, are on the order of thousands of of rad per square
meter. The evolution of RM with frequency suggests that jet bases are either
spherical or conical."