  We analyze 1050 ks of INTEGRAL data of the high mass X-ray binary pulsar 1E
1145.1-6141 to study its properties over a long time baseline, from June 2003
to June 2004, with wide spectral coverage.
  We study three high luminosity episodes, two of them at the system apoastron,
three brightening with lower intensity, two at the periastron, and one extended
period of intermediate luminosity spanning one orbital cycle. We perform timing
analysis to determine the pulse period and pulse profiles at different energy
ranges. We also analyze the broad band phase average spectrum of different
luminosity states and perform phase resolved spectroscopy for the first flare.
  From the timing analysis, we find a pulse period of ~297 s around MJD 53000
with a significant scatter around the mean value. From the spectral analysis we
find that the source emission can be described by an absorbed bremsstrahlung
model in which the electron temperature varies between ~25 and ~37 keV, without
any correlation to luminosity, and the intrinsic absorbing column is constantly
of the order of 10^23 cm^-2. Phase resolved spectral analysis evidences a
different temperature of the plasma in the ascending and descending edges of
the pulse during the first flare. This justifies the pulse maximum shift by
~0.4 phase units between 20 and 100 keV observed in the pulse profiles.
  The comparison with the previous period measurements reveals that the source
is currently spinning-down, in contrast to the long term secular trend observed
so far indicating that at least a temporary accretion disk is formed. The study
of the spectral property variations with respect to time and spin phase
suggests the presence of two emitting components at different temperatures
whose relative intensity varies with time.
