AEGIS-X: The Chandra Deep Survey of the Extended Groth Strip

TL;DR

The AEGIS-X survey provides deep Chandra X-ray observations of the Extended Groth Strip, detecting over 1300 sources with high accuracy, and offers comprehensive multiwavelength counterpart identifications, enhancing the understanding of X-ray sources in this region.

Contribution

This paper introduces an updated data reduction and source detection pipeline for the AEGIS-X survey, resulting in a catalog of 1325 X-ray sources with verified low contamination and extensive multiwavelength counterparts.

Findings

Detected 1325 X-ray sources with high confidence.

Achieved <1.5% spurious source contamination.

Identified optical counterparts for 76% of sources.

Abstract

We present the AEGIS-X survey, a series of deep Chandra ACIS-I observations of the Extended Groth Strip. The survey comprises pointings at 8 separate positions, each with nominal exposure 200ks, covering a total area of approximately 0.67 deg2 in a strip of length 2 degrees. We describe in detail an updated version of our data reduction and point source detection algorithms used to analyze these data. A total of 1325 band-merged sources have been found to a Poisson probability limit of 4e-6, with limiting fluxes of 5.3e-17 erg/cm2/s in the soft (0.5-2 keV) band and 3.8e-16 erg/cm2/s in the hard (2-10 keV) band. We present simulations verifying the validity of our source detection procedure and showing a very small, <1.5%, contamination rate from spurious sources. Optical/NIR counterparts have been identified from the DEEP2, CFHTLS, and Spitzer/IRAC surveys of the same region. Using a likelihood ratio method, we find optical counterparts for 76% of our sources, complete to R(AB)=24.1, and, of the 66% of the sources that have IRAC coverage, 94% have a counterpart to a limit of 0.9 microJy at 3.6 microns (m(AB)=23.8). After accounting for (small) positional offsets in the 8 Chandra fields, the astrometric accuracy of the Chandra positions is found to be 0.8 arcsec RMS, however this number depends both on the off-axis angle and the number of detected counts for a given source. All the data products described in this paper are made available via a public website.