We have created a general catalogue of Active Galactic Nuclei(AGN) selected from optical identifications of X-ray sources using two sources: Hamburg--ROSAT Catalogue(HRC) and Byurakan--Hamburg--ROSAT Catalogue(BHRC). Both contain optical identifications of X-ray sources from ROSAT catalogues based on low-dispersion spectra of Hamburg Quasar Survey(HQS). HRC used ROSAT Bright Source Catalogue (BSC) and BHRC used brighter sources of ROSAT Faint Source Catalogue(FSC), thus extending the sample to count rates of photons CR?0.04ct/s in the area with galactic latitudes |b|?20o and declinations ??0o (the area of HQS). However, HRC and BHRC contain a number of misidentifications and using the recent optical and multiwavelength (MW) catalogues we have revised both samples excluding false AGN and adding new genuine AGN. As a result, a new sample of 4253 X-ray selected AGN was created (ROSAT BSC/FSC AGN). All these sources are either genuine AGN or have been classified as candidate AGN based on HQS low-dispersion spectra. 3352 of them are listed in the 13th version of the Catalogue of QSOs and Active Galaxies (VCV-13) and 387 are in the Multifrequency Catalogue of Blazars (Roma-BZCAT). For these sources we retrieved all MW data (Gamma, X-ray, UV, optical, IR, radio) from recent catalogues and carried out statistical investigations. An attempt to find connections between the radiation fluxes in different bands for different types of sources, and identify their characteristics thus confirming candidate AGN have been done. We have analyzed X-ray properties of these sources to find a limit between normal galaxies and X-ray AGN, in fact hidden AGN.

Areg Mickaelian PI; PhD Leading researcher

Hayk Abrahamyan PhD Researcher

Gurgen Paronyan Researcher

Gor Mikayelyan Researcher

Andranik Sukiasyan Assistant astronomer