Interpretation of Multiwavelength Observations of Nonthermal Extragalactic Radio Sources

摘要

Radio observations of compact extragalactic radio sources study the emission at parsec-scales, and are generally interpreted in terms of a relativistic jet model. The 'inner jet' region that connects the parsec-scale jet with the central engine can only be observed at wavelengths shorter than those in the radio regime, namely the submillimeter to gamma-ray portions of the spectrum. Multiwavelength observations demonstrate that there is a strong relationship between the nonthermal emission at lower and higher frequencies. Future multiwavelength monitoring holds the key to understanding the geometry and physics of the inner jet.