Unveiling the nature of INTEGRAL objects through optical spectroscopy. X. A new multi-year, multi-observatory campaign

摘要

Within the framework of our program (running since 2004) of identification ofhard X-ray INTEGRAL sources through optical spectroscopy, we present theresults concerning the nature of 33 high-energy objects. The data were acquiredwith the use of six telescopes of different sizes and from one on-line archive.The results indicate that the majority of these objects (23 out of 33) areactive galactic nuclei (AGNs), whereas 10 are sources in the local Universewith eight of which in the Galaxy and two in the Small Magellanic Cloud (SMC).Among the identified AGNs, 13 are of Type 1 (i.e., with broad emission lines),eight are of Type 2 (with narrow emissions only), and two are X-ray bright,optically normal galaxies with no apparent nuclear activity in the optical. Sixof these AGNs lie at high redshift (z > 0.5). Concerning local objects, wefound that five of them are Galactic cataclysmic variables, three are high-massX-ray binaries (two of which lying in the SMC), one is a low-mass X-ray binary,and one is classified as a flare star that is likely of RS CVn type. The mainoptical properties and inferred physical characteristics of these sources arepresented and discussed.