Comparison of 3.6 - 8.0 Micron Spitzer/IRAC Galactic Center Survey Point Sources with Chandra X-Ray Point Sources in the Central 40x40 Parsecs

Abstract

We have studied the correlation between 2357 Chandra X-ray point sources in a 40 x 40 parsec field and ~20,000 infrared sources we observed in the corresponding subset of our 2 x 1.4 degree Spitzer/IRAC Galactic Center Survey at 3.6-8.0 um, using various spatial and X-ray hardness thresholds. The correlation was determined for source separations of less than 0.5", 1" or 2". Only the soft X-ray sources show any correlation with infrared point sources on these scales, and that correlation is very weak. The upper limit on hard X-ray sources that have infrared counterparts is <1.7% (3 sigma). However, because of the confusion limit of the IR catalog, we only detect IR sources with absolute magnitudes < ~1. As a result, a stronger correlation with fainter sources cannot be ruled out. Only one compact infrared source, IRS 13, coincides with any of the dozen prominent X-ray emission features in the 3 x 3 parsec region centered on Sgr A*, and the diffuse X-ray and infrared emission around Sgr A* seems to be anti-correlated on a few-arcsecond scale. We compare our results with previous identifications of near-infrared companions to Chandra X-ray sources.

28 pages, 8 Postscript figures (low resolution). Accepted for publication in the ApJ

References in corpus (8)

• Infrared Extinction Toward Nearby Star-Forming Regions
• Multi-wavelength observations of Galactic hard X-ray sources discovered by INTEGRAL. II. The environment of the companion star
• Diffuse, Non-Thermal X-ray Emission from the Galactic Star Cluster Westerlund 1
• Point Sources from a Spitzer IRAC Survey of the Galactic Center
• The K-band Spectrum of The Hot Star in IRS~8: An Outsider in the Galactic Center?
• Discovery of hot supergiant stars near the Galactic center
• A population synthesis study on the faint X-ray sources in the Galactic center region
• Interaction Matrix Element Fluctuations in Ballistic Quantum Dots: Random Wave Model

Cited by in corpus (4)

• Spitzer/IRAC Observations of the Variability of Sgr A* and the Object G2 at 4.5 microns
• Near-Infrared Counterparts to Chandra X-ray Sources toward the Galactic Center. I. Statistics and a Catalog of Candidates
• Near-infrared counterparts of Chandra X-ray sources toward the Galactic Center
• Imprints of Molecular Clouds in Radio Continuum Images