Comments on the hysteresis of the saturation buildup in the axial HGMS configuration

The values of the saturated buildup mass m/sub s/ during the process of deposition-removal of paramagnetic particles in the axial HGMS configuration were studied. When removing particles from a saturated buildup by decreasing the magnetic field H or increasing the flow velocity /spl nu/, a quasiremanence appears concretized in a mass difference /spl Delta/m/sub s/. The mass difference depends on both the field decrease /spl Delta/H and velocity increase /spl Delta//spl nu/. Besides the final state parameters H, /spl nu/, the saturated buildup mass depends also on the deposition history, thus showing a hysteresis phenomenon. The cause of this phenomenon consists in the higher friction force, due to the increased coefficients of static friction between the particles.