Chandra Announcement (Correction): Preliminary Chandra Source Catalog 2.1 Cross-Matched to Optical/IR Catalogs and SDSS Spectroscopy

[Tara Gokas]

Using the NWAY algorithm (Salvato, M.  et al. 2018, MNRAS, 473, 4937), we have crossmatched the set of X-ray sources extracted from the CSC 2.1 production-current database on 14 November 2022 (387k sources) to four catalogs—Gaia DR3, Legacy Survey DR10, PanSTARRS-1, and 2MASS, finding counterparts for 229k CSC 2.1 production current database sources. Cross-matching this table with SDSS DR17 spectroscopy yields more than 17k objects with SDSS spectra, including pipeline classifications and radial velocities. The resulting catalog lists a subset of X-ray information for these sources, includes catalog IDs, positions and magnitudes for all optical/IR matches. We present a README file describing the catalog, and the cross-match catalog itself in FITS and CSV format all posted to the CSC 2 Crossmatch webpage at https://cxc.cfa.harvard.edu/csc/csc_crossmatches.html.