A deep Chandra observation of the interacting star-forming galaxy Arp
  299
  We present results from a 90 ks Chandra ACIS-S observation of the X-ray
luminous interacting galaxy system Arp 299 (NGC 3690/IC 694). We detect 25
discrete X-ray sources with luminosities above 4.0x10^38 erg s^-1 covering the
entire Ultra Luminous X-ray source (ULX) regime. Based on the hard X-ray
spectra of the non-nuclear discrete sources identified in Arp 299, and their
association with young, actively star-forming region of Arp 299 we identify
them as HMXBs. We find in total 20 off-nuclear sources with luminosities above
the ULX limit, 14 of which are point-like sources. Furthermore we observe a
marginally significant deficit in the number of ULXs, with respect to the
number expected from scaling relations of X-ray binaries with the star
formation rate (SFR). Although the high metalicity of the galaxy could result
in lower ULX numbers, the good agreement between the observed total X-ray
luminosity of ULXs, and that expected from the relevant scaling relation
indicates that this deficit could be the result of confusion effects. The
integrated spectrum of the galaxy shows the presence of a hot gaseous component
with kT = 0.72+-0.03 keV, contributing 20% of the soft (0.1-2.0 keV) unabsorbed
luminosity of the galaxy. A plume of soft X-ray emission in the west of the
galaxy indicates a large scale outflow. We find that the AGN in NGC 3690
contributes only 22% of the observed broad-band X-ray luminosity of Arp 299.
