X-ray spectroscopy of the high-mass X-ray binary 4U 1700-37

Abstract

We present the first 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 four times, covering 37% of one 3.41-day orbit. The lightcurve shows strong flares, commonly observed in this source. We focus on three intervals in which the data are not affected by pile up: the eclipse, the eclipse egress and a low-flux part around orbital phase φ ∼ 0.28. We discuss the soft excess, the emission lines observed in eclipse and eclipse egress and the consequences for the size of the ionisation zone.