Russian Researchers Discover 11 New AGNs in All-Sky X-ray Survey – Delhi News Daily

11 new active galactic nuclei were detected in an all-sky X-ray source survey conducted by researchers from the Russian Academy of Sciences. A team led by Grigory Uskov has been on an inspection of the X-ray sources found in the ART-XC telescope of the Spektr-RG (SRG) space observatory. So far, their studies have resulted in the identification of more than 50 AGNs and several cataclysmic variables. A deeper dive into the physical properties and radiation nature of those galaxies will be crucial for a wide range of studies such as statistical insights, refining and testing cosmological models, classification studies etc.

Classification of newly found AGN

According to the recent study published in Astronomy letters, the newly discovered active galactic nuclei from the ARTSS1-5 catalog are categorised as the Seyfert galaxies, seven type 1 (Sy 1), three type 1.9 (Sy 1.9) and one type 2 (Sy 2).

AGN or active galactic nuclei are considered as the most luminous persistent sources of electromagnetic radiation in the universe. These compact regions at the centre of a galaxy are extremely energetic due to accretion onto a supermassive black hole or star formation activity at the galaxy’s center.

Based on their luminosity, AGNs are categorised as Seyfert Galaxies and Quasars. Seyfert galaxies are lower-luminosity AGNs where the host galaxy is clearly visible and emit a lot of infrared radiation, and have broad optical emission lines.

Research findings

The published paper states the 11 newly found galaxies are located relatively nearby, at redshifts of 0.028-0.258. The X-ray luminosities of these sources are within the range of 2 to 300 tredecillion erg/s, therefore typical for AGNs at the present epoch.

The spectrum of one of the new AGNs, designated SRGA J000132.9+240237, is described by a power law with a slope smaller than 0.5, which suggests a strong absorption and a significant contribution of the radiation reflected from the galaxy’s dusty torus. The authors of the paper noted that longer X-ray observations are required to determine the physical properties of this AGN.