Luminous X-Ray Sources in Arp 147
Abstract
The Chandra X-Ray Observatory was used to image the collisional ring galaxy Arp 147 for 42 ks. We detect 9 X-ray sources with luminosities in the range of 1.4 - 7 x 1039 ergs/sec in or near the blue knots of star formation associated with the ring. A source with an isotropic X-ray luminosity of 1.4 x 1040 ergs/sec is detected in the nuclear region of the intruder galaxy. X-ray sources associated with a foreground star and a background quasar are used to improve the registration of the X-ray image with respect to HST high resolution optical images. The intruder galaxy, which apparently contained little gas before the collision, shows no X-ray sources other than the one in the nuclear bulge which may be a poorly fed supermassive black hole. These observations confirm the conventional wisdom that collisions of gas rich galaxies trigger large rates of star formation which, in turn, generate substantial numbers of X-ray sources, some of which have luminosities above the Eddington limit for accreting stellar-mass