Contents
ß ²ultra-luminous sources²
ß different physical classes of X-ray
sources
what they are and how to test the
models
€ case
studies: M83, NGC300, M74, NGC 4449
€ multiwavelength comparisons
ß luminosity and colour
distributions
and what they tells us about
the host galaxy
ß introduction
why studying X-ray sources in
other galaxies