Downstream Ray Tracing in Beam Optics Codes.
Abstract
Tunnel emittance growth in beams is a subtle phenomenon which requires the use of highly accurate simulation codes and methods to achieve reliable results. This report discusses use of self-consistent beam optics codes in studies of emittance growth in very long PPM focused electron beams. A novel method by which a given problem can be accurately solved in a stairstep series downstream is presented. The deformable mesh code is used to simulate a gridded gun focused by a double period magnetic field used in a high power coupled cavity traveling-wave tube. Solution coupling across the boundary is presented in detail. The study also uncovered a fundamental problem with paraxial based codes (Neuman boundary implicit) making their use unsuitable in emittance growth studies. Keywords: Electron beams; Beam optics; Paraxial based codes; Electron optics; Simulation codes; Periodic permanent magnets. (jhd)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1988
- Accession Number
- ADA204895
Entities
People
- Wilfredo B. Reyes
Organizations
- University of Utah