skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Lattice design of a quasi-isochronous ring for a storage-ring FEL

Conference ·
OSTI ID:238752
;  [1];  [2]
  1. Lawrence Berkeley Lab., CA (United States)
  2. Electrotechnical Lab., Ibaraki (Japan)

Design work for a Quasi-Isochronous Ring (QI-Ring) dedicated to Storage Ring FELs in Electrotechnical Laboratory has been completed. The motivation for this work is to shorten the electron bunch length in order to get a high peak current in a compact Storage-Ring (SR). By placing an inverted dipole field in a location where the energy dispersion function is relatively large, one can reduce the momentum compaction factor ({alpha}) and shorten a bunch length in a SR. The main requirements for the QI-Ring are: 1.5GeV maximum beam energy; 80m circumference; two 10m-long dispersion free straight sections for insertion devices. A few meters dispersion free straight sections for RF cavities and injection bumpers; and a wide tune ability in betatron functions and momentum compaction factor ({alpha}). As shown in figure 1, the lattice includes two 49 degree, 3 T superconducting bending magnets to reduce the circumference of the ring, a -8 degree normal inverted dipole magnet (ID), 4 families quadrupole magnets (QF, QD, QFA, QDA), and 3 families sextupole magnets. Each quadrupole family has a specific function: QF & QD control the betatron tunes, and QFA & QDA control the {alpha} and suppress the energy dispersion in a straight section. In this type of ring it is important to compensate the second order momentum compaction factor ({alpha}{sub 2}), so at least three families of sextupoles are required.

Research Organization:
Brookhaven National Lab. (BNL), Upton, NY (United States)
DOE Contract Number:
AC03-76SF00098
OSTI ID:
238752
Report Number(s):
BNL-61982-Absts.; CONF-9508156-Absts.; ON: DE96002729; TRN: 96:013241
Resource Relation:
Conference: 17. international free electron laser conference, New York, NY (United States), 21-25 Aug 1995; Other Information: PBD: [1995]; Related Information: Is Part Of 17th international free electron laser conference and 2nd international FEL users` workshop. Program and abstracts; PB: 300 p.
Country of Publication:
United States
Language:
English