EFFECT OF THE NONUNIFORMITY OF RADIO SOURCES ON ESTIMATES OF THEIR PHYSICAL PARAMETERS

Estimating the physical parameters of nonuniform radio sources in active galactic nuclei (AGN) requires knowledge of the angular dimensions of radio sources at the low frequencies where a steep slope (cutoff) in the low-frequency spectrum (opacity region) is observed. In most compact radio sources, the low-frequency cutoff lies in the meter wavelength range. At present there are no VLBI systems operating at meter wavelengths, so the low-frequency dimensions of compact radio sources in AGN cannot be measured directly. Here we propose a method for estimating the low-frequency angular dimensions of compact radio sources (in the opacity region) based on the shape of their spectra.