X-ray Properties of Young Early Type Galaxies: I. X-ray Luminosity
  Function of LMXBs
  We have compared the combined X-ray luminosity function (XLF) of LMXBs
detected in Chandra observations of young, post-merger elliptical galaxies,
with that of typical old elliptical galaxies. We find that the XLF of the
'young' sample does not present the prominent high luminosity break at LX > 5 x
1038 erg s-1 found in the old elliptical galaxy XLF. The 'young' and 'old' XLFs
differ with a 3{\sigma} statistical significance (with a probability less than
0.2% that they derive from the same underlying parent distribution). Young
elliptical galaxies host a larger fraction of luminous LMXBs (LX > 5 x 1038 erg
s-1) than old elliptical galaxies and the XLF of the young galaxy sample is
intermediate between that of typical old elliptical galaxies and that of star
forming galaxies. This observational evidence may be related to the last
major/minor mergers and the associated star formation.
