MassiveYoungStar-FormingComplexStudyinIR&X-Rays:X-RaySourceCatalog

The Massive Young Star-forming complex Study in Infrared and X-ray (MYStIX) uses data from the Chandra X-Ray Observatory to identify and characterize the young stellar populations in 20 Galactic (d &lt; 4 kpc) massive star-forming regions. In this present study, the X-ray analysis for Chandra ACIS-I observations of 10 of the MYStIX fields is described, and a catalog of &gt; 10,000 X-ray sources is presented in this table. In comparison to other published Chandra source lists for the same regions, the number of MYStIX-detected faint X-ray sources in a region is often doubled. While the higher catalog sensitivity increases the chance of false detections, it also increases the number of matches to infrared stars. X-ray emitting contaminants include foreground stars, background stars, and extragalactic sources. The X-ray properties of sources in these classes are discussed in the reference paper. The X-ray observations were made with the imaging array on the Advanced CCD Imaging Spectrometer (ACIS-I) on board the Chandra X-Ray Observatory. This array of four CCD detectors subtends 17&#39; x 17&#39; on the sky. The number of different Chandra pointings for each region, the total exposures for these pointings, and details of how the observations were taken are provided in Table 1 of the reference paper. Overall, 29 Chandra ObsIDs are included with typical integration times for a pointing of 40 - 100 ks, sufficient to detect most OB stars and lower-mass pre-main-sequence stars down to ~ 0.5 - 1 solar masses for the MYStIX regions. The 10 MYStIX MSFRs treated herein are listed in Table 2 of the reference paper. The data were acquired from the Chandra Data Archive from 2001 Jan to Mar 2008 for 10 MYStIX fields (the Flame Nebula, RCW 36, NGC 2264, the Rosette Nebula, the Lagoon Nebula, NGC 2362, DR 21, RCW 38, Trifid Nebula and NGC 1893). The X-ray photometry is from Broos et al. (2010, ApJ, 714, 1582; ACIS Extract); see also the CCCP, Broos et al. (2011, ApJS, 194, 2). The source significance quantities (fb_prob_no_src, sb_prob_no_src, hb_prob_no_src and prob_no_src_min) are computed using a subset of each source&#39;s extractions chosen to maximize significance (Broos et al. 2010, ApJ, 714, 1582, Section 6.2). The source position and positional uncertainty quantities are computed using a subset of each source&#39;s extractions chosen to minimize the position uncertainty (Broos et al. 2010, ApJ, 714, 1582, Sections 6.2 and 7.1). All other quantities are computed using a subset of each source&#39;s extractions chosen to balance the conflicting goals of minimizing photometric uncertainty and of avoiding photometric bias (Broos et al. 2010, ApJ, 714, 1582, Sections 6.2 and 7). The observed and absorption-corrected energy fluxes and their associated errors and the estimated hydrogen column densities and their uncertainties are derived using non-parametric procedures (XPHOT, Getman et al. 2010, ApJ, 708, 1760). XPHOT assumes the X-ray spectral shapes of young, low-mass stars, which come from coronal X-ray emission. XPHOT quantities will therefore be unreliable for high-mass stars, for which X-ray emission is associated with the stellar wind. This table was created by the HEASARC in January 2014 based on &lt;a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJS/209"&gt;CDS Catalog J/ApJS/209&lt;/a&gt; 27 file xmystix.dat. This is a service provided by NASA HEASARC .

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Organization: National Aeronautics and Space Administration