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We present a catalog of 1415 X-ray sources identified in the Norma arm regionChandra survey (NARCS), which covers a 2 deg x 0.8 deg region in the directionof the Norma spiral arm to a depth of $\approx$20 ks. Of these sources, 1130are point-like sources detected with $\geq3\sigma$ confidence in at least oneof three energy bands (0.5-10, 0.5-2, and 2-10 keV), five have extendedemission, and the remainder are detected at low significance. Since mostsources have too few counts to permit individual classification, they aredivided into five spectral groups defined by their quantile properties. Weanalyze stacked spectra of X-ray sources within each group, in conjunction withtheir fluxes, variability, and infrared counterparts, to identify the dominantpopulations in our survey. We find that $\sim$50% of our sources are foregroundsources located within 1-2 kpc, which is consistent with expectations fromprevious surveys. Approximately 20% of sources are likely located in theproximity of the Scutum-Crux and near Norma arm, while 30% are more distant, inthe proximity of the far Norma arm or beyond. We argue that a mixture ofmagnetic and nonmagnetic CVs dominates the Scutum-Crux and near Norma arms,while intermediate polars (IPs) and high-mass stars (isolated or in binaries)dominate the far Norma arm. We also present the cumulative number countdistribution for sources in our survey that are detected in the hard energyband. A population of very hard sources in the vicinity of the far Norma armand active galactic nuclei dominate the hard X-ray emission down to$f_X\approx10^{-14}$ erg cm$^{-2}$ s$^{-1}$, but the distribution curveflattens at fainter fluxes. We find good agreement between the observeddistribution and predictions based on other surveys.

The Norma Arm Region Chandra Survey: X-ray Populations in the Spiral Arms