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arXiv · 1208.1510

The Chandra Local Volume Survey: The X-ray Point Source Catalog of NGC 300

Breanna Binder·Benjamin F. Williams·Michael Eracleous·Terrance J. Gaetz·Paul P. Plucinsky·Evan D. Skillman·Julianne J. Dalcanton·Scott F. Anderson·Daniel R. Weisz·Albert K. H. Kong
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Abstract

We present the source catalog of a new Chandra ACIS-I observation of NGC 300 obtained as part of the Chandra Local Volume Survey. Our 63 ks exposure covers ~88% of the D25 isophote (R~6.3 kpc) and yields a catalog of 95 X-ray point sources detected at high significance to a limiting unabsorbed 0.35-8 keV luminosity of ~10^36 erg s^-1. Sources were cross-correlated with a previous XMM-Newton catalog, and we find 75 "X-ray transient candidate" sources that were detected by one observatory, but not the other. We derive an X-ray scale length of 1.7+/-0.2 kpc and a recent star formation rate of 0.12 Msun yr^-1, in excellent agreement with optical observations. Deep, multi-color imaging from the Hubble Space Telescope, covering ~32% of our Chandra field, was used to search for optical counterparts to the X-ray sources, and we have developed a new source classification scheme to determine which sources are likely X-ray binaries, supernova remnants, and background AGN candidates. Finally, we present the X-ray luminosity functions (XLFs) at different X-ray energies, and we find the total NGC 300 X-ray point source population to be consistent with other late-type galaxies hosting young stellar populations (<50 Myr). We find XLF of sources associated with older stellar populations has a steeper slope than the XLF of X-ray sources coinciding with young stellar populations, consistent with theoretical predictions.

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Breanna Binder, Benjamin F. Williams, Michael Eracleous, Terrance J. Gaetz, Paul P. Plucinsky, Evan D. Skillman, Julianne J. Dalcanton, Scott F. Anderson, Daniel R. Weisz, Albert K. H. Kong. 2012-08-07. The Chandra Local Volume Survey: The X-ray Point Source Catalog of NGC 300. https://doi.org/10.1088/0004-637x%2F758%2F1%2F15

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