Exploring a New Population of Compact Objects: X-ray and IR Observations of the Galactic Centre

TL;DR

This study combines X-ray and infrared observations to identify and classify faint X-ray sources in the Galactic Center, aiming to understand their nature and contribution to the Galactic binary population.

Contribution

It presents a comprehensive multi-wavelength observational campaign and a methodology for identifying and spectroscopically analyzing candidate X-ray source counterparts in the Galactic Center.

Findings

Cross-matched X-ray sources with IR counterparts using astrometry.

Derived magnitudes and colors for candidate counterparts.

Planned spectroscopic survey to identify accreting binaries.

Abstract

I describe the IR and X-ray observational campaign we have undertaken for the purpose of determining the nature of the faint discrete X-ray source population discovered by Chandra in the Galactic Center (GC). Data obtained for this project includes a deep Chandra survey of the Galactic Bulge; deep, high resolution IR imaging from VLT/ISAAC, CTIO/ISPI, and the UKIDSS Galactic Plane Survey (GPS); and IR spectroscopy from VLT/ISAAC and IRTF/SpeX. By cross-correlating the GC X-ray imaging from Chandra with our IR surveys, we identify candidate counterparts to the X-ray sources via astrometry. Using a detailed IR extinction map, we are deriving magnitudes and colors for all the candidates. Having thus established a target list, we will use the multi-object IR spectrograph FLAMINGOS-2 on Gemini-South to carry out a spectroscopic survey of the candidate counterparts, to search for emission line signatures which are a hallmark of accreting binaries. By determining the nature of these X-ray sources, this FLAMINGOS-2 Galactic Center Survey will have a dramatic impact on our knowledge of the Galactic accreting binary population.