Star Formation in Nearby Clouds (SFiNCs) Probable Cluster Members Catalog

The Star Formation in Nearby Clouds (SFiNCs) project is aimed at providing a detailed study of the young stellar populations and of star cluster formation in the nearby 22 star-forming regions (SFRs) for comparison with the authors&#39; earlier MYStIX survey of richer, more distant clusters. As a foundation for the SFiNCs science studies, in the reference paper homogeneous data analyses of the Chandra X-ray and Spitzer mid-infrared (MIR) archival SFiNCs data are described, and the resulting catalogs of over 15,300 X-ray and over 1,630,000 mid-infrared point sources are presented. On the basis of their X-ray/infrared properties and spatial distributions, nearly 8500 point sources have been identified as probable young stellar members of the SFiNCs regions. Compared to the existing X-ray/mid-infrared publications, the SFiNCs member list increases the census of YSO members by 6%-200% for individual SFRs and by 40% for the merged sample of all 22 SFiNCs SFRs. Sixty-five X-ray observations of the 22 SFiNCs SFRs made with the imaging array on the Advanced CCD Imaging Spectrometer (ACIS) were extracted from the Chandra archive (spanning from 2000 January to 2015 April). See Tables 1 and 2 of the reference paper for the list of SFRs and the log of Chandra ACIS observations, respectively. The final Chandra-ACIS catalog for the 22 SFiNCs SFRs comprises 15,364 X-ray sources (presented in Tables 3 and 4 and section 3.2 of the reference paper, and available as the HEASARC table, SFINCSXRAY). To obtain MIR photometry for X-ray objects and to identify and measure MIR photometry for additional non-Chandra disky stars that were missed in previous studies of the SFiNCs regions (typically faint YSOs), the authors have reduced the archived Spitzer-IRAC data by homogeneously applying the MYStIX-based Spitzer-IRAC data reduction methods of Kuhn et al. (2013, ApJS, 209, 29) to the 423 Astronomical Object Request (AORs) data sets for the 22 SFiNCs SFRs (listed in Table 5 of the reference paper). As in MYStIX, the SFiNCs IRAC source catalog retains all point sources with the photometric signal-to-noise ratio &gt; 5 in both [3.6] and [4.5] um channels. This catalog covers the 22 SFiNCs SFRs and their vicinities on the sky and comprises 1,638,654 IRAC sources with available photometric measurements for 100%, 100%, 29%, and 23% of these sources in the 3.6, 4.5, 5.8, and 8.0um bands, respectively (see table 6 and section 3.4 of the reference paper). Source position cross-correlations between the SFiNCs Chandra X-ray source catalog and an IR catalog, either the &quot;cut-out&quot; IRAC or 2MASS, were made using the steps described in section 3.5 of the reference paper. Using the ensemble of X-ray and infrared data that they have obtained, the authors selected probable YSOs in the 22 SFRs using selection criteria described in section 4.1 of the reference paper. Tables 7 and 8 of the reference paper provide the list of 8,492 SFiNCs probable cluster members (SPCMs: but see below for a caveat on this number) and their main IR and X-ray properties (see section 4 of the reference paper). This present HEASARC table comprises the contents of these two tables. A fuller list of the X-ray properties of the X-ray-detected SPCMs is available in the HEASARC&#39;s SFINCSXRAY table (q.v.). This table was created by the HEASARC in September 2017 based on the &lt;a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJS/229/28"&gt;CDS Catalog J/ApJS/229/28&lt;/a&gt; files table7.dat (the IR photometry of the SFiNCs probable cluster members) and table8.dat (the main X-ray and other properties of the SFiNCs probable cluster members). This is a service provided by NASA HEASARC .

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Organization: National Aeronautics and Space Administration