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We present the results of our identification of eight objects from apreliminary catalogue of X-ray sources detected in the 4-12 keV energy band bythe Mikhail Pavlinsky ART-XC telescope aboard the SRG observatory during itsfirst all-sky survey. Three of them (SRGAJ005751.0+210846,SRGAJ014157.0-032915,SRGAJ232446.8+440756) have been discovered by ART-XC, while five were alreadyknown previously as X-ray sources, but their nature remained unknown. The lastfive sources have also been detected in soft X-rays by the eROSITA telescope ofthe SRG observatory. Our optical observations were carried out at the 1.6-mAZT-33IK telescope of the Sayan Observatory and the 1.5-m Russian-Turkishtelescope (RTT-150). All of the investigated objects have turned out to beactive galactic nuclei (AGNs) at redshifts from 0.019 to 0.283. Six of them areSeyfert 2 galaxies(including one Seyfert 1.9 galaxy), one(SRGAJ005751.0+210846) is a "hidden" AGN (in an edge-on galaxy), and one(SRGAJ224125.9+760343) is a narrow-line Seyfert 1 galaxy. The latter object ischaracterized by a high X-ray luminosity (~(2-13)*10^44 erg/s in the 4-12 keVband) and,according to our black hole mass estimate (~2*10^7 M_sun), anaccretion rate close to the Eddington limit. All three AGNs discovered by theART-XC telescope (which are not detected by the eROSITA telescope) arecharacterized by a high absorption column density (N_H > 3*10^23 cm^-2). Theresults obtained confirm the expectations that the ART-XC telescope is anefficient instrument for searches of heavily obscured and other interestingAGNs in the nearby (z<0.3) Universe. The SRG all-sky survey will last for morethan 3 years more, which will allow many such objects to be discovered.

astronomy letters

Optical identification of active galactic nucleus candidates detected by  the Mikhail Pavlinsky ART-XC telescope aboard the SRG observatory during the  all-sky X-ray survey