The nature of active galaxies based on their radio properties

In this paper, we investigate radio properties of active galaxies taken from the reference [Véron‐Cetty & Véron (2010)] catalog. The galaxies are limited to magnitudes in the range of 12m − 19m. We have cross‐correlated the list with radio catalogs and selected those galaxies that have data on six or more radio fluxes at different wavelengths. As a result, we have 198 galaxies that satisfy these conditions. Using SDSS DR15, we have obtained 96 spectroscopic identifications of the 198 objects. After the classification, 85% of the 96 objects have changed their types. Available data on the classification of these objects and our classification showed that 56.7% of them are Seyfert galaxies. For all the objects, we have built radio spectra and estimated radio spectral indices. As a result, we obtain α‾=−0.6089±0.056(α‾Seyfert=−0.6013±0.027, α‾LINER=−0.5955±0.025, α‾HII=−0.6672±0.039, α‾Comp.=−0.7128±0.043). We discuss the radio properties of active galaxies based on their radio spectral indices.