We report on the near-infrared matches, drawn from three surveys, to the 1640 unique X-ray sources detected by Chandra in the Galactic Bulge Survey (GBS). This survey targets faint X-ray sources in the bulge, with a particular focus on accreting compact objects. We present all viable counterpart candidates and associate a false alarm probability (FAP) to each near-infrared match in order to identify the most likely counterparts. The FAP takes into account a statistical study involving a chance alignment test, as well as considering the positional accuracy of the individual X-ray sources. We find that although the star density in the bulge is very high, ̃90 per cent of our sources have an FAP cent, indicating that for most X-ray sources, viable near-infrared counterparts candidates can be identified. In addition to the FAP, we provide positional and photometric information for candidate counterparts to ̃95 per cent of the GBS X-ray sources. This information in combination with optical photometry, spectroscopy and variability constraints will be crucial to characterize and classify secure counterparts. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.
Publication Source (Journal or Book title)
Monthly Notices of the Royal Astronomical Society
Greiss, S., Steeghs, D., Jonker, P., Torres, M., Maccarone, T., Hynes, R., Britt, C., Nelemans, G., & Gänsicke, B. (2014). Near-infrared counterparts to the galactic bulge survey x-ray source population. Monthly Notices of the Royal Astronomical Society, 438 (4), 2839-2852. https://doi.org/10.1093/mnras/stt2390