Optical eclipses and precession effects in the HD 153919=4U 1700-37 X-ray binary system

Characteristics of the HD 153919=4U1700-37 X-ray binary system are discussed. The long-period (P=32sup(d). 46) variability of the amplitude and shape of the optical light curves of the X-ray binary HD 153919 has been discovered from the analysis of all published photometric data. This periodicity is due to the eclipses of the optical star 0 6f by the ''precessing'' accretion structure in the vicinity of the neutron star. The variability of the equivalent width of the emission line He2 lambda 4686 and the amplitude and shape of radial velocity curves with the period 32sup(d).46 imply that the ''precession'' of the accretion structure is caused by the precession of the rotational axis of the optical star 0 6 f. This phenomenon is similar to that which is observed in the HZ Her and SS 433 systems. Optical light curve corrected for the eclipse effects has the amplitude of the ellipsoidal light variability 0sup(m).0.27-0sup(m). 035 and is in good agreement with the duration of the X-ray eclipses and with the spectroscopic data. The depth of the eclipse is about 0sup(m).04. The estimations of the parameters of the system are obtained. It is shown that the parameter of the Roche Lobe filling for the optical star 0 6f is μ<1. The supernova explosion in a binary system is discussed as the main cause of the precession of the rotational axis of the optical star, and related problems