Coffee talks
Friday 18/10/2019 @ 11:30, Sala riunioni quarto piano
Jee Won Lee (Korea Astronomy and Space Science Institute), "Variability properties of blazars in multi-wavelength"
The Korean VLBI Network (KVN) is the first Very Long Baseline facility in Korea operated by the Korea Astronomy and Space Science Institute. The KVN has a unique quasi-optics system which is possible to observe at for frequencies simultaneously. This capability gives advantages in studying the physics of AGN jets with multi-frequency observations. In this talk, I will briefly introduce the KVN and its key science program called iMOGABA (Interferometric Monitoring of Gamma-ray Bright active galactic nuclei) and present studies of variability properties of blazars in multi-wavelength. Blazars are a sub-class of AGN. One of the characteristics of blazars shows various time scales from days to years of variability in flux density as well as polarized emission in multi-wavelength. Therefore the studies of variability in multi-wavelength allow us to study the emission mechanism of AGN jets, and magnetic field strength which plays an important role in forming a jet. Here, I mainly present the observation results of the variability at various time scales of a BL Lac object S5 0716+714 from radio to gamma-ray.