Localized chromaticity correction of low-beta insertions in storage rings
- Stanford Linear Accelerator Center, Menlo Park, CA (United States)
- Lawrence Berkeley Lab., CA (United States)
The correction of the chromaticity of low-beta insertions in the storage rings is usually made with sextupole lenses in the ring`s arcs. When decreasing the beta functions at the insertion point (IP), this technique becomes fairly ineffective, since it fails to properly correct the higher order chromatic aberrations. Here we consider the approach where the chromatic effects of the quadrupole lenses generating low beta functions at the IP are corrected locally with two families of sextupoles, one family for each plane. Each family has two pairs of sextupoles which are located symmetrically on both sides of the IP. The sextupole-like aberrations of individual sextupoles are eliminated by utilizing optics forming a -I transformation between sextupoles in the pair. The optics also includes bending magnets which preserve equal dispersion functions at the two sextupoles in each pair. At sextupoles in one family, the vertical beta function is made large and the horizontal is made small. The situation is reversed in the sextupoles of the other family. The betatron phase advances from the IP to the sextupoles are chosen to eliminate a second order chromatic aberration. The application of the localized chromatic correction is demonstrated using as an example the lattice design for the Low Energy Ring of the SLAC/LBL/LLNL PEP-II B Factory.
- Research Organization:
- SLAC National Accelerator Lab., Menlo Park, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC03-76SF00515; AC03-76SF00098; AS03-76ER70285
- OSTI ID:
- 139798
- Report Number(s):
- SLAC-PUB-6197; LBL-33276; ESG-232; CONF-930511-453; ON: DE93041082; TRN: 93:023946
- Resource Relation:
- Conference: PAC `93: international particle accelerator conference, Washington, DC (United States), 17-20 May 1993; Other Information: PBD: Apr 1993
- Country of Publication:
- United States
- Language:
- English
Similar Records
Local chromatic correction scheme for LER of PEP-II
Local chromatic correction scheme for LER of PEP-II