A comparison and benchmark of two electron cloud packages

Lebrun, Paul L.G. ; Amundson, James F. ; Spentzouris, Panagiotis G. ; /Fermilab ; Veitzer, Seth A. ; /Tech-X, Boulder

Fermi National Accelerator Laboratory

关键词: 43 Particle Accelerators, 99 General And Miscellaneous//Mathematics, Computing, And Information Science;    Electrostatics;    Accelerators, Computing;    Computerized Simulation;    Particle Beams;   

DOI  :  10.2172/1034441
RP-ID  :  FERMILAB-TM-2524-APC
RP-ID  :  AC02-07CH11359
RP-ID  :  1034441

美国|英语

来源: UNT Digital Library

【 摘 要 】

We present results from precision simulations of the electron cloud (EC) problem in the Fermilab Main Injector using two distinct codes. These two codes are (i)POSINST, a F90 2D+ code, and (ii)VORPAL, a 2D/3D electrostatic and electromagnetic code used for self-consistent simulations of plasma and particle beam problems. A specific benchmark has been designed to demonstrate the strengths of both codes that are relevant to the EC problem in the Main Injector. As differences between results obtained from these two codes were bigger than the anticipated model uncertainties, a set of changes to the POSINST code were implemented. These changes are documented in this note. This new version of POSINST now gives EC densities that agree with those predicted by VORPAL, within {approx}20%, in the beam region. The root cause of remaining differences are most likely due to differences in the electrostatic Poisson solvers. From a software engineering perspective, these two codes are very different. We comment on the pros and cons of both approaches. The design(s) for a new EC package are briefly discussed.