Beam-based determination of the offset of Booster {gamma}{sub T} quads

Xi Yang, Charles M. Ankenbrandt and James MacLachlan

Fermi National Accelerator Laboratory

关键词: 43 Particle Accelerators;    Quadrupoles;    Alignment;    Performance;    Particle Boosters;   

RP-ID  :  FERMILAB-Tm-2254
RP-ID  :  AC02-76CH03000
RP-ID  :  825278

美国|英语

来源: UNT Digital Library

【 摘 要 】

Twelve pulsed {gamma}{sub T} quads have been installed in the Booster to provide fast transition crossing. The less time the beam stays in the non-adiabatic period near transition, the less the longitudinal emittance grows. From the past experience, the {gamma}{sub T} quads are not well aligned relative to the usual closed orbit. Quad steering can cause beam loss and a dispersion wave after transition. To make the {gamma}{sub T} quads routinely operational, procedures for finding the center of the beam relative to the quads and centering the beam through all of them are very important. A program, which uses the difference in the closed orbits when {gamma}{sub T} quads are on and off and calculates the offsets of the beam relative to {gamma}{sub T} quads, has been developed and tested. A radial orbit offset (ROF) of about 3 mm has been experimentally determined to be nearly the optimal radial position for centering the beam through all the {gamma}{sub T} quads, thereby eliminating the immediate need for repositioning the quads.