
Accession Number : ADA190899
Title : Enhanced Channel Tracking Due to BeamGenerated Magnetic Fields,
Corporate Author : MISSION RESEARCH CORP ALBUQUERQUE NM
Personal Author(s) : Welch, D R ; Godfrey, B B
PDF Url : ADA190899
Report Date : 10 Jun 1986
Pagination or Media Count : 45
Abstract : The complete frozenfield Maxwell equations are used to study the tracking behavior of an electron beam in a channel. The three type of channels considered contain conductivity, reduced density or a combination of both. The analytic work includes the derivation of the tracking force for a beam propagating entirely inside a square conductivity channel. The resulting expression reduces to E. Lee's electrostatic expression in the limit of small conductivity. However, for finite conductivity, magnetic tracking is dominant near the head of the beam, particularly for short risetime beams. The numerical work using the threedimensional simulation code IPROP shows high values for channel tracking with large optimal initial conductivities (roughly 1 * 10 to the 10th power scaler conductivity).For all three types of channels, tracking forces of or = 20 gauss are calculated for fastrise 10kA pencil beams in a 1cm channel. Trumpetshaped beams require larger channel radii to produce significant tracking. Forces of approximately 5 gauss are calculated for a 5cm offset channel with 3cm radius. This work suggests tracking forces may be an order of magnitude greater than previously thought.
Descriptors : *CHANNELS, *ELECTRON BEAMS, *MAGNETIC FIELDS, *BEAM STEERING, CODING, DENSITY, ELECTROSTATICS, NUMERICAL METHODS AND PROCEDURES, RADIUS(MEASURE), REDUCTION, SIMULATION, THREE DIMENSIONAL, TRACKING, MAXWELLS EQUATIONS, ELECTRICAL CONDUCTIVITY
Subject Categories : Nuclear Physics & Elementary Particle Physics
Distribution Statement : APPROVED FOR PUBLIC RELEASE