Numerical simulation of intense-beam experiments at LLNL and LBNL

Abstract

We present intense-beam simulations with the WARP code that are being carried out in support of the Heavy-Ion Fusion experimental programs at Lawrence Livermore National Laboratory (LLNL) and Lawrence Berkeley National Laboratory (LBNL). The WARP code is an electrostatic particle-in-cell code with an extensive hierarchy of simulation capabilities. Two experiments are analyzed. First, simulations are presented on an 80 keV, 2 mA K + bent transport channel at LLNL that employs an alternating-gradient lattice of magnetic quadrupoles for beam focusing and electric dipoles for beam bending. Issues on dispersion-induced changes in beam quality on the transition from straight- to bent-lattice sections are explored. The second experiment analyzed is a 2 MeV, 800 mA, driver-scale injector and matching section at LBNL that is based on a K + source and an alternating-gradient lattice of electrostatic quadrupoles biased to accelerate, focus, and match the beam. Issues on beam quality, space-charge waves, and beam hollowing are explored.