Optical and near-infrared observations of new INTEGRAL galactic sources Original Research Article

The INTEGRAL satellite has discovered many sources, the nature of most being still unknown. Only a multi-wavelength approach, including optical and near-infrared observations, may allow to constrain their nature. Several of these sources, apparently located in the Norma arm, share common X-ray properties, in particular a huge intrinsic absorption, probably by cold matter. The best studied source is IGR J16318-4848, for which we summarize here our optical/near-infrared observations, and for which we propose an identification as a High mass X-ray binary, the massive component being an sgB[e] star. There are indications that other sources in the Norma arm are binary systems with massive and rare stars, surrounded by complex envelopes or cocoons.