Total Flux Density Variations in Extragalactic Radio Sources: Observations and211 Analysis

摘要

This doctoral thesis presents observations and analysis of extragalactic radio211u001esources. The sources in question are radio-loud active galactic nuclei, namely 211u001equasars, BL Lac objects and radio galaxies. They were observed at high radio 211u001efrequencies and in gamma-rays. The radio observations were then analyzed by model 211u001efitting and statistical methods, and further compared with the gamma-ray data. 211u001eThe aim was to study individual source properties as well as the properties of 211u001eclasses of sources. A flux-limited complete sample of bright, flat-spectrum 211u001eextragalactic radio sources was constructed, together with a database of all 211u001eavailable VLBI observations. The purpose of the sample is to find suitable 211u001ecandidates for millimeter and space VLBI observations. The sample has been 211u001emonitored both in Metsaehovi and at the SEST telescope in Chile.