  The formation and evolution of low-mass X-ray binaries (LMXBs) is not well
understood. The properties of a population of LMXBs depend on a number of
uncertain aspects of binary evolution, and population studies offers a
relatively new way of probing binary interactions. We have studied the shape of
the faint end of the X-ray luminosity function (LF) of LMXBs in nearby galaxies
with Chandra and in the Milky Way using the Swift all-sky monitor. We find a
clear difference between the LF of LMXBs in globular clusters (GCs) and those
outside, with a relative lack of faint GC sources. This indicates a difference
in the composition of the two populations.

High Energy Astrophysical Phenomena