What Powers Ultraluminous<i>IRAS</i>Galaxies?
What Powers Ultraluminous<i>IRAS</i>Galaxies?
We present an ISO SWS and ISOPHOT-S, mid-infrared spectroscopic survey of 15 ultra-luminous IRAS galaxies. We combine the survey results with a detailed case study, based on near-IR and mm imaging spectroscopy, of one of the sample galaxies (UGC 5101). We compare the near- and mid-IR characteristics of these ultra-luminous …