Error compensation in insertion-region magnets
In heavy ion storage rings, intra-beam scattering (IBS) between high charge state ions results in a large beam emittance during storage. The ultimate machine performance depends on achieving the highest possible magnetic field quality and alignment accuracy in the insertion-region (IR) triplet magnets during low-{beta} operation when the beam size is the largest in the triplets. Therefore, effective compensation of magnet construction errors and misalignments is crucial. Heavy-ion beams (Au{sup 79+} will be accelerated and stored for 10 hours in the Relativistic Heavy Ion Collider (RHIC) at the energy of 100 GeV/u in two separated rings consisting of superconducting magnets. Due to strong IBS, the transverse beam emittance grows from 10{pi} mm-mr at injection to more than 40{pi} mm-mr at storage. Dipoles and riplets of quadrupoles of large bore are placed on both sides of the six interaction points (IP). In order to maximize the luminosity at two IPs with proposed experiments, the nearby triplets are designed to enable the collision {beta}-function to be reduced to {beta} = 1 m. Consequently, the rms transverse beam size becomes large at the triplets ({beta}{sub max} = 1400 m), increasing from {sigma} = 2.3 mm to 4.7 mm during the period of storage. At the end of storage, the 5{sigma} beam size becomes about 71% of the coil radius (65 mm). The goal if IR triplet error compensation is to ensure satisfactory magnetic field quality and beam long-term stability up to this 5{sigma} radius.
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC02-76CH00016
- OSTI ID:
- 220456
- Report Number(s):
- BNL-62611; CONF-9510138-5; ON: DE96007742; TRN: 96:011294
- Resource Relation:
- Conference: LHC `95: international workshop on single particle effects in large hadron colliders, Montreux (Switzerland), 15-21 Oct 1995; Other Information: PBD: [1995]
- Country of Publication:
- United States
- Language:
- English
Similar Records
Stochastic cooling and intra-beam scattering in RHIC
Interaction region analysis for a high-field hadron collider