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arXiv · 2003.13710

The deep Chandra survey in the SDSS J1030+0524 field

R. Nanni·R. Gilli·C. Vignali·M. Mignoli·A. Peca·S. Marchesi·M. Annunziatella·M. Brusa·F. Calura·N. Cappelluti·M. Chiaberge·A. Comastri·K. Iwasawa·G. Lanzuisi·E. Liuzzo·D. Marchesini·I. Prandoni·P. Tozzi·F. Vito·G. Zamorani·C. Norman
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Abstract

We present the X-ray source catalog for the 479 ks Chandra exposure of the SDSS J1030+0524 field, that is centered on a region that shows the best evidence to date of an overdensity around a z > 6 quasar, and also includes a galaxy overdensity around a Compton-thick Fanaroff-Riley type II radio galaxy at z = 1.7. Using wavdetect for initial source detection and ACIS Extract for source photometry and significance assessment, we create preliminary catalogs of sources that are detected in the full, soft, and hard bands, respectively. We produce X-ray simulations that mirror our Chandra observation to filter our preliminary catalogs and get a completeness level of > 91% and a reliability level of 95% in each band. The catalogs in the three bands are then matched into a final main catalog of 256 unique sources. Among them, 244, 193, and 208 are detected in the full, soft, and hard bands, respectively. This makes J1030 field the fifth deepest extragalactic X-ray survey to date. The field is part of the Multiwavelength Survey by Yale-Chile (MUSYC), and is also covered by optical imaging data from the Large Binocular Camera (LBC) at the Large Binocular Telescope, near-IR imaging data from the Canada France Hawaii Telescope WIRCam, and Spitzer IRAC. Thanks to its dense multi-wavelength coverage, J1030 represents a legacy field for the study of large-scale structures around distant accreting supermassive black holes. Using a likelihood ratio analysis, we associate multi-band counterparts for 252 (98.4%) of the 256 Chandra sources, with an estimated reliability of 95%. Finally, we compute the cumulative number of sources in each X-ray band, finding that they are in general agreement with the results from the Chandra Deep Fields.

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R. Nanni, R. Gilli, C. Vignali, M. Mignoli, A. Peca, S. Marchesi, M. Annunziatella, M. Brusa, F. Calura, N. Cappelluti, M. Chiaberge, A. Comastri, K. Iwasawa, G. Lanzuisi, E. Liuzzo, D. Marchesini, I. Prandoni, P. Tozzi, F. Vito, G. Zamorani, C. Norman. 2020-03-30. The deep Chandra survey in the SDSS J1030+0524 field. https://doi.org/10.1051/0004-6361%2F202037914

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