Accelerator Seminar DATE: 2004-12-21 16:00 - 17:00 PLACE: KEK Building 1, 1st floor, Meeting Room TITLE: Heavy Ion Inertial Fusion Program in US and CONTACT: Ken TAKAYAMA takayamapost.kek.jp SPEAKER: S.M.Lund  (LBNL/LLNL) LANGUAGE: English ABSTRACT: The WARP code is an extensive self-consistent electrostatic PIC　Code developed to simulate ion beams with high space-charge intensity for Heavy Ion Fusion and other applications. WARP Consists of a family of self-consistent moment, 2D(r-z axisymmetric and x-y transverse slice), and 3D models with an extensive hierarchy of field-solvers and particle movers that work with bent or "warped" lattices and common diagnostics. Numerically intensive routines in fortran are linked to the　Python interpreter. Many diagnostic and code control structures are coded in Python to allow flexible operation and code steering. This structure allows models and numerical methods to be utilized under a common framework, thereby facilitating checks of idealizations and numerical methods. Here we highlight recent advances in WARP modeling capabilities and overview a particular advance in the understanding of intense beam properties learned from WARP. Modeling advances include:adaptive mesh refinement enabling high resolution simulations that are being applied to injectors; complex geometry field solver with multiple emitting structures, apertures, beams, and self-consistent particle scraping to enable simulation of multi-beam injectors with merging; generalized particle loading to construct initial distributions consistent with limited experimentally measured distribution projections; and a hybrid mover for electrons and ions that interpolates between a usual Boris advance and a drift kinetic model to enable more efficient e cloud simulations. To highlight physics insights provided by the code, we highlight WARP modeling of the High Current Transport Experiment(HCX) at LBNL that illustrate problems associated with lattice transitions and aperturing (scraping) of intense beams. Back