Chandra localisation and optical/NIR follow-up of Galactic X-ray sources

TL;DR

This study uses Chandra and follow-up optical/NIR observations to identify and confirm counterparts of eleven Galactic X-ray sources, clarifying their associations and nature.

Contribution

It provides new precise Chandra localizations and optical/NIR identifications for several X-ray sources, resolving previous ambiguities and establishing first associations.

Findings

Confirmed associations for four sources with optical/NIR counterparts.

Ruled out previous counterparts for two sources, suggesting new ones.

First optical/NIR associations established for J16293-4603 and XTE J1743-363.

Abstract

We investigate a sample of eleven Galactic X-ray sources recently discovered with INTEGRAL or RXTE with the goal of identifying their optical and/or near-infrared (NIR) counterpart. For this purpose new Chandra positions of nine objects are presented together with follow-up observations of all the targets in the optical and NIR. For the four sources IGR J16194-2810, IGRJ 16479-4514, IGR J16500-3307 and IGR J19308+530, the Chandra position confirms an existing association with an optical/NIR object, while for two sources (XTE J1716-389 and 18490-0000) it rules out previously proposed counterparts indicating new ones. In the case of IGR J17597-220, a counterpart is selected out of the several possibilities proposed in the literature and we present the first association with an optical/NIR source for J16293-4603 and XTE J1743-363. Moreover, optical/NIR observations are reported for XTE J1710-281 and IGR J17254-3257: we investigate the counterpart to the X-ray sources based on their XMM-Newton positions. We discuss the nature of each system considering its optical/NIR and X-ray properties.