Search

We present the results of our identification of eight objects from the preliminary catalogue of X-ray sources detected in the 4-12 keV energy band by the Mikhail Pavlinsky ART-XC telescope onboard the SRG observatory during the first all-sky survey. Three of them (SRGA J005751.0+210846, SRGA J014157.0-032915, SRGA J232446.8+440756) have been discovered by the ART-XC telescope, while five have already been known previously as X-ray sources, but their nature has remained unestablished. The last five sources have also been detected in soft X-rays by the eROSITA telescope of the SRG observatory. Our optical observations have been carried out at the 1.6-m AZT-33IK telescope of the Sayan Observatory and the 1.5-m Russian-Turkish telescope (RTT-150). All of the investigated objects have turned out to be active galactic nuclei (AGNs) at redshifts from 0.019 to 0.283. Six of them are Seyfert 2 galaxies (including one Seyfert 1.9 galaxy), one (SRGA J005751.0+210846) is a "hidden" AGN (in an edge-on galaxy), and one (SRGA J224125.9+760343) is a narrow-line Seyfert 1 galaxy. The latter object is characterized by a high X-ray luminosity (similar to(2 - 13) x 10(44) erg s(-1) in the 4-12 keV band) and, according to our black hole mass estimate (similar to 2 x 10(7) M-circle dot), an accretion rate close to the Eddington limit. All three AGNs discovered by the ART-XC telescope (which are not detected by the eROSITA telescope) are characterized by a high absorption column density (N-H greater than or similar to 3 x 10(23) cm(-2)). The results obtained confirm the expectations that the ART-XC telescope is an efficient instrument in searching for heavily obscured and other interesting AGNs in the nearby (z less than or similar to 0.3) Universe. The SRG sky survey will last for another 3 years or more, which must allow many such objects to be discovered.