The Chandra Deep Wide-Field Survey: A New Chandra Legacy Survey in the Boo ̈tes Field I. X-ray Point Source Catalog, Number Counts and Multi-Wavelength Counterparts

We present a new, ambitious survey performed with the Chandra X-ray Observatory of the 9.3 deg2 Bo¨otes field of the NOAO Deep Wide-Field Survey. The wide field probes a statistically representative volume of the Universe at high redshift. The Chandra Deep Wide-Field Survey exploits the excellent sensitivity and angular resolution of Chandra over a wide area, combining 281 observations spanning 15 years, for a total exposure time of 3.4 Ms, and detects 6891 X-ray point sources down to limiting fluxes of 4:7 10􀀀16, 1:5 10􀀀16, and Corresponding author: Alberto Masini [e-mail] 2 MASINI ET AL. 910􀀀16 erg cm􀀀2 s􀀀1, in the 0:5􀀀7 keV, 0:5􀀀2 keV, and 2􀀀7 keV bands, respectively. The robustness and reliability of the detection strategy is validated through extensive, state-of-the-art simulations of the whole field. Accurate number counts, in good agreement with previous X-ray surveys, are derived thanks to the uniquely large number of point sources detected, which resolve 65:0 12:8% of the cosmic X-ray background between 0:5􀀀2 keV and 81:011:5% between 2􀀀7 keV. Exploiting the wealth of multi-wavelength data available on the field, we assign redshifts to 94% of the X-ray sources, estimate their obscuration and derive absorptioncorrected luminosities. We provide an electronic catalog containing all the relevant quantities needed for future investigations.