Speaker
Description
Blazars are highly variable radio-loud AGN, with jets closely aligned with the line-of-sight. These sources can be observed over the entire electromagnetic spectrum and are well monitored at, e.g., radio or gamma-ray wavelengths. The eROSITA telescope with its all-sky survey presents a unique opportunity to obtain an unbiased view of the blazar population in the X-ray band. By matching the first eROSITA all-sky survey (eRASS1) with catalogs containing blazars and blazar candidates we find roughly 6400 matches with eROSITA detected sources. About 1400 X-ray sources, of which 800 are associated with confirmed blazars and more than 600 are consistent with candidate blazars based on their multiwavelength properties, exhibit enough counts to allow spectral analysis. We present diagnostics such as the distribution of the X-ray photon indices, which show different behavior for different blazar subclasses. For roughly 500 of these sources eROSITA gives us the first X-ray detection to date. Due to eROSITA’s sensitivity, it is also possible to reliably constrain the blazar X-ray log(N)-log(S), which is consistent with theoretical expectations. In addition, we relate the X-ray data to other wavelengths, which provides further information on the spectral energy distribution of blazars and their luminosities. The catalog also provides a sound foundation to exploit the rich eROSITA dataset in the future for blazar science.
