This PDF file contains the front matter associated with SPIE Proceedings Volume 7121, including the Title Page, Copyright information, Table of Contents, Introduction, and the Conference Committee listing.

Mathematical simulation of electron-optical systems often requires high accuracy of electric and magnetic field calculation and smoothness of its results in the entire computational volume, not just near the symmetry axis. This requirement is necessary to construct aberrational series with respect to an arbitrary principle trajectory. To solve this problem, we propose an effective method for modeling non-linear magnetostatic systems. The method is based on decomposition of the computational domain into three parts, in which we employ different calculation approaches: the finite-element method and the boundary element method. Solution joining at the subdomains' boundaries is guaranteed by the use of common iteration procedure of minimizing the energy functional. The developed method allows calculating magnetic field with higher accuracy and less calculation difficulties.

The method of calculation of intensive charged beams on rectangular quasistructured grids is offered. The grids are constructed in two stages: first the computational domain is broken by a uniform rectangular macrogrid into subdomains, and then in each macrocell is constructed uniform rectangular locally-modified subgrid. The basis of this method is made with construction and the solving of system of the linear algebraic equations concerning values of an electric field potential in nodes of the grid covering a interface boundary of subdomains. The suggested method is direct as in it there are no iterations on subdomains. In the conclusion the basic properties of the considered approach are listed.

Detailed computer simulation of field emission sources has been carried out using the CP03D program. The program computes the potential distribution, the field distribution and electron trajectories in arbitrary electrostatic systems. The calculations have revealed very strong dependence of the electrostatic field on the cathode tip diameter. The field dependence on the distance between the cathode tip and an anode plate is also essential. The size of the anode aperture affects rather little the electrostatic field strength.

Some methodological features of the solving of optimization problems of intensive charged particle beams on an example of a test problem about a Pierce's gun are considered. The behavior of the purpose function, its sensitivity to a change of the parameters, and step by step approach to an optimization is investigated.

From known invariant solutions of non-stationary space-charge-flow equations some variants are revealed which describe stationary beams with axial symmetry. New solutions in elementary functions are represented. The problem of beam forming electrodes is solved for previously unknown electron flow.

The exact solution of dense electron beam butt-ends formation is formulated. The objects are cylinders of finite length, trancated cones, cylindrical and conical rings, toroids, spheres and ellipsoids which are divided from Brillouin flow with single non-zero azimuthal component of velocity.

Electron optics model of a cathode lens consisting of hyperboloid of rotation and a plane called "a needle above plane" is presented. The most important result is asymptotic crossover radius changing in wide range of tip radius changing and the half angle of the apex. The results can be useful for the description of thermionic guns for nanolithography.

The principle of the least action states, that the motion of objects on optimum trajectories conjugates to the underload expenditure of activity. In the canonical approach this statement is reduced to searching extreme activity. For the immediate proof of the underload expenditure of activity on optimum trajectories the relevant mathematical algorithm in the basis of which bottom the concept of optimum time exponents lays is offered. Using this algorithm, various modes of a motion of charged particles are explored: the harmonic motion, a motion in the homogeneous force field, a motion in a central force field and a motion on inertia. The terrain clearance minimum under the rate of flux of activity for the harmonic motions is detected.

It is shown that a length-limited axially-symmetrical electron cylinder has focal properties in relation to ion beams. The example of the calculation of system parameters for focusing of a helium ion intensive beam is given.

Following the recent tendencies of the microwave technology process, the demand has risen now for high-power L- & S-band magnetrons to be used in mobile equipment. Development of high-power packaged magnetrons using the recent progress in the design of compact permanent magnet systems seems to be the best solution to minimize overall equipment weight and dimensions.

The investigation of the widespread 0D fluid model Ref. 1 - Ref. 8 for calculation of ion charge-state distributions (CSD) in electron cyclotron resonance (ECR) ion source Ref. 1 is presented. The modification of this model that allows one to describe the confinement and accumulation processes of highly charged ions in ECR plasma for gas mixing case more precisely is discussed. The description of the calculation technique for the time confinement of ions and electrons based on the theory of Pastukhov is also given, videlicet - calculation of confinement times during two stage minimization scheme of special functionals. The results obtained by this approach have been compared with available experimental data.

The pulsed injector of the low energy positrons for positron accumulator LEPTA has been constructed and tested at JINR. The injector is based on ²²Na radioactive source. Positrons from the source are moderated in the solid neon and injected into positron trap, where they are accumulated during about 80 seconds. For injection the positrons are extracted by the pulsed electric field and accelerated up to the required energy. The injector will generate positrons of the energy of up to 10 keV at relative energy spread of 2•10^-3, intensity of 10⁸ - 10⁹ particles per pulse and at injection pulse duration of 300 nsec. The cryogenic source of slow positrons has been tested with a test isotope ²²Na of the initial activity of 80 MBk. The continuous slow positron beam with average energy spread of 1.2 eV, width of a spectrum 1 eV has been obtained. The achieved moderator efficiency is about 1%. The accumulation process in the positron trap was investigated with electron flux. The life time of the electrons in the trap, τ_life ≥ 80 s and capture efficiency ε ~ 0.4 have been obtained. The maximum number of the accumulated particle was N_exper = 2*10⁸ at the initial flux of 5•10⁶ electrons per sec. The dynamics of slow positrons (electrons) in the injector and physics of the particle storage process are discussed in the report. The work is supported by RFBR grant No. 05-02-16320, the president of Russia Federation grant (MK-3948.2007.2) for supporting of young scientists and leading sceintific schools.

The cooling stacking injection is one of widely used injection method applied for formation of a high intensive cooled ion beams in the synchrotrons. The maximal available ion intensity in the synchrotron at this injection is defined by the injection intensity, the ion lifetime and the cooling-stacking efficiency. The formation of the high intensive beams is restricted by their instability leading to strong ion lifetime reduction. The experimental investigations, simulations of the cooling-stacking injection and stability of the high intensive cooled ion beams are discussed.

It is shown that numerical algorithms for region near cathode and thermal gap are non-adequate to usual hydrodynamical beam model under Ρ - and Τ - regime of emission with zero start velocity. This is the reason of non-trustworthiness for beam calculations in case of linear compression L ≥ 20. The method is formulated which may eliminate disbalance between theoretical beam model and its numerical realization. In the most contemporary devices with dense electron beams the thermocathodes are used as source of electrons. Two important problems demand their solution in this case: design and technology for cathode heater with thermal gap between cathode and focusing electrode; design of electron-optical system for electron beam needed parameters. This article is devoted to discussion of numerical results in region near cathode edge. These results are obtained thanks to trajectory analysis programs which use the hydrodynamical beam model and Ρ - or Τ - regime of emission for space-charge-flow with zero start velocity. The discussion is continuation of adequacy and accuracy investigations for numerical models of dense electron beams.

The problem of identification of parameters direct gap semiconductors is considered at use of dependence of intensity monochromatic cathodoluminescence from electron beam energy and realization of low level of excitation of a signal. It is shown, that realization of a method of the least squares leads to system of the nonlinear algebraic equations which decision essentially depends on a choice of initial approach. Taking into account it some conditions of correct processing of experimental data for identification of required parameters of semiconductors are defined.

The theory of electron dynamic diffraction interaction with the field of crystal lattice was developed. It was made using wave electron optics ideas and achievements of transfer function theory.