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arXiv · 1408.6579

The Chandra Cygnus OB2 Legacy Survey: Design and X-ray Point Source Catalog

Nicholas J. Wright·Jeremy J. Drake·Mario G. Guarcello·Tom L. Aldcroft·Vinay L. Kashyap·Francesco Damiani·Joe DePasquale·Antonella Fruscione
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Abstract

The Cygnus OB2 association is the largest concentration of young and massive stars within 2 kpc of the Sun, including an estimated 65 O-type stars and hundreds of OB stars. The Chandra Cygnus OB2 Legacy Survey is a large imaging program undertaken with the Advanced CCD Imaging Spectrometer onboard the Chandra X-ray Observatory. The survey has imaged the central 0.5 deg^2 of the Cyg OB2 association with an effective exposure of 120ks and an outer 0.35 deg^2 area with an exposure of 60ks. Here we describe the survey design and observations, the data reduction and source detection, and present a catalog of 8,000 X-ray point sources. The survey design employs a grid of 36 heavily (~50%) overlapping pointings, a method that overcomes Chandra's low off-axis sensitivity and produces a highly uniform exposure over the inner 0.5 deg^2. The full X-ray catalog is described here and is made available online.

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Nicholas J. Wright, Jeremy J. Drake, Mario G. Guarcello, Tom L. Aldcroft, Vinay L. Kashyap, Francesco Damiani, Joe DePasquale, Antonella Fruscione. 2014-08-27. The Chandra Cygnus OB2 Legacy Survey: Design and X-ray Point Source Catalog. https://arxiv.org/abs/1408.6579

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