Observation of phase slip when superfluid spin current passage in 3He-B

Experimental conditions, where superfluid spin current transferring magnetization along the narrow channel is defined by magnetization precession phase difference at the channel ends, are created in superfluid 3He-B. Critical current, at which precession phase slips in the channel, is observed. Spin superfluid current behaviour in the channel is similar to that of superconducting current in a weak chain and of 4He superfluid current in a minor whole