Multiwavelength study of Chandra X-ray sources in the Antennae
Article first published online: 12 OCT 2010
© 2010 The Authors. Journal compilation © 2010 RAS
Monthly Notices of the Royal Astronomical Society
Volume 410, Issue 2, pages 890–898, January 2011
How to Cite
Clark, D. M., Eikenberry, S. S., Brandl, B. R., Wilson, J. C., Carson, J. C., Henderson, C. P., Hayward, T. L., Barry, D. J., Ptak, A. F. and Colbert, E. J. M. (2011), Multiwavelength study of Chandra X-ray sources in the Antennae. Monthly Notices of the Royal Astronomical Society, 410: 890–898. doi: 10.1111/j.1365-2966.2010.17487.x
- Issue published online: 30 DEC 2010
- Article first published online: 12 OCT 2010
- Accepted 2010 August 5. Received 2010 August 4; in original form 2010 July 14
- galaxies: starburst;
- galaxies: star clusters: general;
- X-rays: binaries
We use Wide-field InfraRed Camera (WIRC) infrared (IR) images of the Antennae (NGC 4038/4039) together with the extensive catalogue of 120 X-ray point sources to search for counterpart candidates. Using our proven frame-tie technique, we find 38 X-ray sources with IR counterparts, almost doubling the number of IR counterparts to X-ray sources that we first identified. In our photometric analysis, we consider the 35 IR counterparts that are confirmed star clusters. We show that the clusters with X-ray sources tend to be brighter, Ks≈ 16 mag, with (J−Ks) = 1.1 mag.
We then use archival Hubble Space Telescope (HST) images of the Antennae to search for optical counterparts to the X-ray point sources. We employ our previous IR-to-X-ray frame-tie as an intermediary to establish a precise optical-to-X-ray frame-tie with <0.6 arcsec rms positional uncertainty. Due to the high optical source density near the X-ray sources, we determine that we cannot reliably identify counterparts. Comparing the HST positions to the 35 identified IR star cluster counterparts, we find optical matches for 27 of these sources. Using Bruzual–Charlot spectral evolutionary models, we find that most clusters associated with an X-ray source are massive, and young, ∼ 106 yr.