A novel approach to the synthesis of the electromagnetic field distribution in a chain of coupled resonators

A novel approach to the synthesis of the electromagnetic field distribution in a chain of coupled resonators has been developed. This approach is based on the new matrix form of the solutions of the second-order difference equations. If a chain of coupled resonators can be described by the second-order difference equation for amplitudes of expansion of the electromagnetic field, two linearly independent solutions can be constructed on the basis of the solutions of nonlinear Riccaty equation. Setting the structure of one solution, from the Riccaty equation we can find the electrodynamical characteristics of resonators and coupling holes, at which the desired distribution of amplitudes is realized. On the base of this approach we considered the problem of separation of the electromagnetic field into forward and backward components in the inhomogeneous chain of resonators. It was shown that in the frame of considered model such separation is not defined uniquely.Comment: 20 pages, 6 figure

Fast code CASCIE (Code for Accelerating Structures -Coupled Integral Equations). Test Results

Results of testing the fast CASCIE (Code for Accelerating Structures - Coupled Integral Equations) code developed as an analytical-numerical tool for studying the properties of inhomogeneous structured waveguides are presented. We have used this code to numerically tune the resonator chain, which is very similar to the classic 3m SLAC accelerating structure. During testing, we discovered a problem that, in our opinion, was overlooked in the development of the accelerating sections, namely the appearance of a constant phase shift when determining the dimensions of the resonator radii from the characteristics of homogeneous structures. This issue is particularly relevant in the development of short accelerating structures.Comment: 11 pages, 1 table, 22 figure