Unveiling the nature of IGR J16283−4838^⋆

L. J. Pellizza^1,2, S. Chaty³ and N. E. Chisari^1⋆⋆

¹ Instituto de Astronomía y Física del Espacio, C.C. 67, Suc. 28, (1428), Buenos Aires, Argentina
e-mail: pellizza@iafe.uba.ar
² Consejo Nacional de Investigaciones Científicas y Tećnicas (CONICET), Argentina
³ Laboratoire AIM (UMR 7158 CEA/DSM-CNRS-Université Paris Diderot) Irfu/Service d’Astrophysique, Centre de Saclay, Bât. 709, 91191 Gif-sur-Yvette Cedex, France

Received: 7 May 2010
Accepted: 14 September 2010

Abstract

Context. One of the most striking discoveries of the INTEGRAL observatory is the existence of a previously unknown population of X-ray sources in the inner arms of the Galaxy. The investigations of the optical/NIR counterparts of some of them have provided evidence that they are highly absorbed high mass X-ray binaries hosting supergiants.

Aims. We aim to identify the optical/NIR counterpart of one of the newly discovered INTEGRAL sources, IGR J16283−4838, and determine the nature of this system.

Methods. We present optical and NIR observations of the field of IGR J16283−4838, and use the astrometry and photometry of the sources within it to identify its counterpart. We obtain its NIR spectrum, and its optical/NIR spectral energy distribution by means of broadband photometry. We search for the intrinsic polarization of its light, and its short and long-term photometric variability.

Results. We demonstrate that this source is a highly absorbed HMXB located beyond the Galactic center, and that it may be surrounded by a variable circumstellar medium.