Simulation of three-dimensional electrostatic field configuration in wire chambers: A novel approach

Three-dimensional field configuration has been simulated for a simple wire chamber consisting of one anode wire stretched along the axis of a grounded square cathode tube by solving numerically the boundary integral equation of the first kind. A closed-form expression of potential due to charge distributed over flat rectangular surface has been invoked in the solver using Green's function formalism leading to a nearly exact computation of electrostatic field. The solver has been employed to study the effect of several geometrical attributes such as the aspect ratio (gimel = 11d, defined as the ratio of the length 1 of the tube to its width d) and the wire modeling on the field configuration. Detailed calculation has revealed that the field values deviate from the analytic estimates significantly when the is reduced to 2 or below. The solver has demonstrated the effect of wire modeling on the accuracy of the estimated near-field values in the amplification region. The thin wire results can be reproduced by the polygon model incorporating a modest number of surfaces (>= 32) in the calculation with an accuracy of more than 99%. The smoothness in the three-dimensional field calculation in comparison to fluctuations produced by other methods has been observed. (c) 2006 Elsevier B.V. All rights reserved.