  We present results of a monitoring campaign of the high-mass X-ray binary
system 4U 1700-37/HD 153919, carried out with XMM-Newton in February 2001. The
system was observed at four orbital phase intervals, covering 37% of one
3.41-day orbit. The lightcurve includes strong flares, commonly observed in
this source. We focus on three epochs in which the data are not affected by
photon pile up: the eclipse, the eclipse egress and a low-flux interval in the
lightcurve around orbital phase phi ~0.25. The high-energy part of the
continuum is modelled as a direct plus a scattered component, each represented
by a power law with identical photon index (alpha ~1.4), but with different
absorption columns. We show that during the low-flux interval the continuum is
strongly reduced, probably due to a reduction of the accretion rate onto the
compact object. A soft excess is detected in all spectra, consistent with
either another continuum component originating in the outskirts of the system
or a blend of emission lines. Many fluorescence emission lines from
near-neutral species and discrete recombination lines from He- and H-like
species are detected during eclipse and egress. The detection of recombination
lines during eclipse indicates the presence of an extended ionised region
surrounding the compact object. The observed increase in strength of some
emission lines corresponding to higher values of the ionisation parameter xi
further substantiates this conclusion.

Astrophysics