Recent results from observations of 4U1700-37 using SAS-3

SAS-3 observations of a complete orbital cycle (approximately 3.5 d) of the X-ray source 4U1700-37 are presented. A persistent, approximately sinusoidal modulation of approximately 60% amplitude is present in the data at 97 m. Satellite orbital effects are ruled out by using other detectors pointed away from the source but sampled at the same time. The effect of such a long rotation period (if indeed the period is rotational) on current ideas involving accretion torques and stellar wind is discussed.