Multi-wavelength observations of serendipitous Chandra sources

Gandhi, P.; Crawford, C.S.; Fabian, A.C.; Wilman, R.J.; Johnstone, R.M.; Barger, A.J.; Cowie, L.L.

Abstract

We describe progress in a programme to study a sample of sources typical of those which contribute a large fraction of the hard X-ray background. The sources are selected from the fields of approximately 10 ks Chandra cluster observations with follow-up in the near-infrared and optical. The X-ray data indicate that many of these are powerful, obscured sources. Two hard objects which are lensed by the cluster are good candidates for X-ray type-2 quasars, with luminosities of the order 10^{44}-10^{45} erg s^{-1} and obscuring column densities of the order 10^{23} cm^{-2}. We find that the sources are bright in the infra-red (K typically 17-18). From Keck optical spectra and photometric redshifts, we find that the host galaxies are consistent with being early-type, massive hosts at redshifts ranging from 0.2 to 3, with median redshift approximately 1.5. The two obscured quasars also have mid-infrared detections and 850-micron upper-limits implying that the surrounding dust is at warm-to-hot temperatures (T of the order of 1000 K).

Citation

Gandhi, P., Crawford, C., Fabian, A., Wilman, R., Johnstone, R., Barger, A., & Cowie, L. (2001). Multi-wavelength observations of serendipitous Chandra sources. In D. M. Neumann, & J. T. V. Tran (Eds.),

• Presentation Conference Type: Conference Paper (Published)
• Conference Name: Clusters of Galaxies and the High Redshift Universe Observed in X-rays
• Start Date: Mar 10, 2001
• End Date: Mar 17, 2001
• Publication Date: 2001
• Deposit Date: Apr 9, 2018
• Public URL: https://durham-repository.worktribe.com/output/1145614
• Publisher URL: http://adsabs.harvard.edu/abs/2001cghr.confE..63G