CASA Seminar

Thursday, May 25, 2006, 3:30 PM
ARC, 231/233

Advances in Electromagnetic Modeling: Advanced Algorithms,
Self-consistency, and Parallelism

John R. Cary
Tech-X Corp. and University of Colorado, Boulder

Multiple advances in algorithms, computation, and computational hardware have made
electromagnetic calculations of large, complex systems possible. So-called charge-conserving
algorithms allow fully self-consistent computations, in which the self-generated wake fields affect
the dynamics of the particles generating the fields. Cut-cell (or embedded) boundaries allow the
accurate computation of modes for complex shapes, such as crab cavities with multiple
resonators and both low-order mode dampers and high-order mode dampers. Inclusion of
emission processes enables the computation of multipactoring and similar effects. New implicit
algorithms that conserve charge are stable for any time step. These allow one to compute
systems with structures small compared with the characteristic wavelength of the system in
reasonable time. Algorithms that parallelize well allow one to take advantage of the largest
computational hardware. This talk will discuss these algorithmic and computational advances,
their implementation in VORPAL,** a flexible, object-oriented, massively parallel modeling
application, and their application to beam physics. Example computations for cavities,
photoinjectors, and compact acceleration will be presented.

* Work in collaboration with J. Amundson, R. Busby, D. L. Bruhwiler, R. Busby, J. Carlsson, D. A. Dimitrov, P. Messmer, C. Nieter, N. Sizemore, D. N. Smithe, P. Spentzouris, P. Stoltz, R. M. Trines, S. Veitzer, W.-L. Wang, G. Werner
** C. Nieter and J. R. Cary, "VORPAL: a versatile plasma simulation code", J. Comp. Phys. 196, 448-472 (2004).

Talk Slides: (Slides)