The Serendipitous Extragalactic X-Ray Source Identification (SEXSI) Program: II. Optical Imaging
Abstract
The Serendipitous Extragalactic X-ray Source Identification (SEXSI) Program is designed to expand significantly the sample of identified extragalactic hard X-ray sources at intermediate fluxes, 1e-13 erg/cm2/s < S_(2-10 keV) < 1e-15 erg/cm2/s. SEXSI, which includes sources derived from more than 2 sq deg of Chandra images, provides the largest hard X-ray-selected sample yet studied, offering an essential complement to the Chandra Deep Fields (total area ~0.2 sq deg). In this paper we describe R-band optical imaging of the SEXSI fields from the Palomar, MDM, and Keck observatories. We have identified counterparts, or derived flux limits for nearly 1000 hard X-ray sources. Using the optical images, we derive accurate source positions. We investigate correlations between optical and X-ray flux, and optical flux and X-ray hardness ratio. We also study the density of optical sources surrounding X-ray counterparts, as well as the properties of optically-faint, hard X-ray sources.
Cite
@article{arxiv.astro-ph/0409012,
title = {The Serendipitous Extragalactic X-Ray Source Identification (SEXSI) Program: II. Optical Imaging},
author = {Megan E. Eckart and Elise S. Laird and Daniel Stern and Peter H. Mao and David J. Helfand and Fiona A. Harrison},
journal= {arXiv preprint arXiv:astro-ph/0409012},
year = {2009}
}
Comments
30 pages, 8 figures; accepted to ApJS