Siberian Snakes Based on Transverse Magnetic Fields to Preserve and Control Proton Polarization in the NICA Collider

Siberian snakes based on helix and dipole magnets have been proposed to preserve proton polarization during acceleration in the NICA collider and to control the polarization direction throughout the entire energy range of the experiment. Unlike a solenoidal snake, whose field integral increases proportionally with momentum, the field integral in these snakes on transverse fields remains nearly constant with increasing energy. The advantages of the proposed snakes include their compactness and acceptable closed-orbit deviations at low energies. The results of numerical simulations of spin dynamics during proton acceleration up to 13.5 GeV in the NICA accelerator complex are presented.