The Massive Star-Forming Regions Omnibus X-Ray Catalog, Second
  Installment
  We present the second installment of the Massive Star-forming Regions (MSFRs)
Omnibus X-ray Catalog (MOXC2), a compilation of X-ray point sources detected in
Chandra/ACIS observations of 16 Galactic MSFRs and surrounding fields. MOXC2
includes 13 ACIS mosaics, three containing a pair of unrelated MSFRs at
different distances, with a total catalog of 18,396 point sources. The MSFRs
sampled range over distances of 1.3 kpc to 6 kpc and populations varying from
single massive protostars to the most massive Young Massive Cluster known in
the Galaxy. By carefully detecting and removing X-ray point sources down to the
faintest statistically-significant limit, we facilitate the study of the
remaining unresolved X-ray emission. Through comparison with mid-infrared
images that trace photon-dominated regions and ionization fronts, we see that
the unresolved X-ray emission is due primarily to hot plasmas threading these
MSFRs, the result of feedback from the winds and supernovae of massive stars.
The 16 MSFRs studied in MOXC2 more than double the MOXC1 sample, broadening the
parameter space of ACIS MSFR explorations and expanding Chandra's substantial
contribution to contemporary star formation science.
