Abstract
In an accelerator or storage ring for polarized protons, "Siberian snakes" may be inserted in the lattice in order to stabilize the spin dynamics, i.e. to prevent betatron oscillations and orbit distortions from depolarizing the beam. This is accomplished by inserting an odd number Np of pairs of snakes, spaced π/Np apart in orbit azimuth; each snake is a spin rotator that rotates the spin by exactly 180 degrees about a precession axis in the horizontal plane. The precession axes of the two snakes of a pair should be exactly 90 degrees apart (e.g. longitudinal and transverse horizontal, or ± 45 degrees from longitudinal). The preferred choice in most cases is ±45 degrees. For RHIC, one pair of snakes (Np = l) is planned, 180 degrees apart with ±45 degree axes; in the case of the Tevatron, Np = 3(six snakes) is envisaged, with the snakes spaced 60 degrees apart.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have