Теория и расчет электростатических электронных зеркал с учетом релятивистских эффектов

Using the central particle method, the equations of the trajectory of charged particles in an axisymmetric electrostatic mirror are obtained with an accuracy of the third order of smallness inclusive with account for relativistic effects. The conditions for spatial focusing and the coefficients of spatial aberrations in the Gaussian plane of the mirror image are determined with account for relativism. By means of numerical calculations, conditions for simultaneous elimination of spherical and axial chromatic aberrations are determined, taking into account relativistic effects, in an axisymmetric electrostatic mirror when the object plane of the mirror is aligned with its focal plane. It is shown that account for high particle velocities leads both to a shift in the position of the Gaussian image plane and a change in the focusing quality.

A Straight-Forward Method of Moments Procedure to Solve the Time Domain Integral Equation Applicable to PEC Bodies via Triangular Patch Modeling

In this work, a simple and straight-forward method of moments solution (MOM) procedure is presented to obtain the induced current distribution on an arbitrarily-shaped conducting body illuminated by a Gaussian plane wave directly in the time domain using a patch modeling approach. The method presented in this work, besides being stable, is also capable of handling multiple excitation pulses of varying frequency content incident from different directions in a trivial manner. The method utilizes standard Rao-Wilton-Glisson (RWG) functions and simple triangular functions for the space and time variables, respectively, for both expansion and testing. The method adopts conventional MOM and requires no further manipulation invariably needed in standard time-marching methods. The moment matrix generated via this scheme is a block-wise Toeplitz matrix and, hence, the solution is extremely efficient. The method is validated by comparing the results with the data obtained from the frequency domain solution. Several simple and complex numerical results are presented to validate the procedure.

Высокодисперсионные электростатические зеркала вращательной симметрии с времяпролетной фокусировкой по энергии третьего порядка

Expressions describing the time of flight of charged particles taking into account time-of-flight chromatic aberrations in electrostatic mirrors of rotational symmetry are presented. The conditions of time-of-flight focusing by particle energy up to the third order inclusively in the three-electrode mirrors, the electrodes of which are coaxial cylinders of equal diameter, were determined by numerical calculations. Various modes of operation of such mirrors are considered: 1) space-time-of-flight focusing in the Gaussian plane of the mirror; 2) space-time-of-flight focusing in the focal plane of the mirror; 3) time-of-flight focusing in telescopic mode; 4) time-of-flight focusing in collimator mode. The results of calculations are presented for two fundamental solutions of the equation of paraxial trajectories. One of these solutions describes trajectories whose direct and reverse branches coincide, and the second solution describes trajectories whose direct and reverse branches are symmetrical with respect to the axis of symmetry of the field. It is shown that the time-of-flight dispersion of the mirror by mass, determined on the basis of the second solution, is several times higher than that obtained on the basis of the first solution for all modes of its operation.

Open Resonator System for Reflectarray Elements Characterization

An open resonator system is proposed in this work to study the phase behavior of reflectarrays cells. The characterization of the single reflectarray element is performed by assuming a Gaussian plane wave normally incident on an infinite periodic array of identical radiating elements. An equivalent circuit model is properly derived for the open cavity including the reflectarray test structure, in order to retrieve the phase design curve of the single reflectarray element. K-band experimental validations are presented and discussed to show the effectiveness of the approach.