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arXiv · 0809.1349

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

E. S. Laird·K. Nandra·A. Georgakakis·J. A. Aird·P. Barmby·C. J. Conselice·A. L. Coil·M. Davis·S. M. Faber·G. G. Fazio·P. Guhathakurta·D. C. Koo·V. Sarajedini·C. N. A. Willmer
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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.

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E. S. Laird, K. Nandra, A. Georgakakis, J. A. Aird, P. Barmby, C. J. Conselice, A. L. Coil, M. Davis, S. M. Faber, G. G. Fazio, P. Guhathakurta, D. C. Koo, V. Sarajedini, C. N. A. Willmer. 2008-09-08. AEGIS-X: The Chandra Deep Survey of the Extended Groth Strip. https://doi.org/10.1088/0067-0049/180/1/102

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