The AGS with four helical magnets

Tsoupas, N. ; Huang, H. ; MacKay, W.W. ; Roser, T. ; Trbojevic, D.

Brookhaven National Laboratory (BNL) Relativistic Heavy Ion Collider

关键词: Betatrons;    Beam Injection;    Relativistic Heavy Ion Collider;    Modifications;    43 Particle Accelerators;   

DOI  :  10.2172/973140
RP-ID  :  BNL--91115-2010-IR
RP-ID  :  DE-AC02-98CH10886
RP-ID  :  973140

美国|英语

来源: UNT Digital Library

【 摘 要 】

The idea of using multiple partial helical magnets was applied successfully to the AGS synchrotron, to preserve the proton beam polarization. In this paper we explore in details the idea of using four helical magnets placed symmetrically in the AGS ring. This modification provides many advantages over the present setup of the AGS that uses two partial helical magnets. First, it provides a larger 'spin tune gap' for the placement of the vertical betatron tune of the AGS during acceleration, second, the vertical spin direction during the beam injection and extraction is closer to vertical, third, the symmetric placement of the snakes allows for a better control of the AGS optics, and for reduced values of the beta and eta functions, especially near injection, fourth, the optical properties of the helical magnets also favor the placement of the horizontal betatron tune in the 'spin tune gap', thus eliminating the horizontal spin resonances. In this paper we provide results on the spin tune and on the optics of the AGS with four partial helical magnets, and we compare these results with the present setup of the AGS that uses two partial helical magnets.