Elimination of resonances by Siberian snakes

Polarized particles in a circular accelerator or storage ring undergo spin precession in a coordinate system rotating with the circulation frequency. A Siberian snake is a device, consisting of a sequence of horizontal and vertical deflecting magnets inserted into a straight section, which rotates the spin by 180/sup 0/ about a horizontal axis. It causes the orbit to snake around; the magnets must be such that the net deflection of the orbit by the snake is zero. 6 references.