[SLAC] [SLAC Pubs and Reports]
SLAC-PUB-7913
FEL Trajectory Analysis for the VISA Experiment
Abstract
The Visual to Infrared SASE Amplifier (VISA) [1] FEL is designed to
achieve saturation at radiation wavelengths between 800 and 600 nm
with a 4-m pure permanent magnet undulator. The undulator comprises
four 99-cm segments each of which has four FODO focusing cells
superposed on the beam by means of permanent magnets in the gap
alongside the beam. Each segment will also have two beam position
monitors and two sets of x-y dipole correctors. The trajectory
walk-off in each segment will be reduced to a value smaller than the
rms beam radius by means of magnet sorting, precise fabrication, and
post-fabrication shimming and trim magnets. However, this leaves
possible inter-segment alignment errors. A trajectory analysis code
has been used in combination with the FRED3D [2] FEL code to simulate
the effect of the shimming procedure and segment alignment errors on
the electron beam trajectory and to determine the sensitivity of the
FEL gain process to trajectory errors. The paper describes the
technique used to establish tolerances for the segment alignment.
Full Text
PDF
Compressed PostScript
More Information
Full bibliographic data for this document, including its complete author list,
is (or soon will be) available from SLAC's
SPIRES-HEP
Database.
Please report problems with this file to
posting@slac.stanford.edu.
The SLAC preprint inventory is provided by the
SLAC Technical Publications Department.
Page generated 04 Apr 2001 @ 15:08 PDT by htmlme.pl