P. Zhukova

Investigation of contactless electron transmission through dielectric channels

The effect of the contactless transmission (guiding) of 10 keV electrons through cylindrical dielectric channels and planar channels formed by glass plates is studied. The capture and propagation of an electron beam along the channel axis, usual in these cases, are observed in the experiments with two plates. The deviation of the reflection angle from the specular angle and its dependence on the plate length and beamcurrent value under beam reflection from a single plate are investigated.

Studying the interaction of 10-keV electrons with a dielectric surface

The grazing incidence interaction of a 10-keV electron beam with a planar surface of plexiglass is studied experimentally. Moreover, the electron passage through flat channels formed by such surfaces is investigated. The experiments reveal the presence of a guiding effect of the electron passage as in the case of a glass surface. However, there are some features, such as the existence of an initial elevation angle for the case of negative inclination angles of the plate. The formation of self-consistent charge on the surface of the plexiglass and its drain when the current is turned off occur more slowly than on the glass surface. This fact points to the difference in the surface conductivity of insulators.

Investigation of the guiding effect of 10-keV electrons using planar dielectric surfaces

The effect of guiding a 10-keV electron beam using dielectric plates is studied. It is shown that the electron beam after interaction with the insulator surface is deflected by this surface in different ways depending on a variety of grounding schemes of the front and back sides of plexiglass and aluminum-oxide plates. The dependence of the deflection of the beam from the plexiglass plates at different angle positions on the incident electron-beam current value is studied.

Quantum theory for coupled harmonic oscillators with exponentially changing masses

The classical solution is obtained for the system of two coupled harmonic oscillators with exponentially decaying mass. Using the Feynman path-integral method of quantization an exact propagator for the corresponding quantum system is derived.

CONCERNING CONTACTLESS ION TRANSMISSION IN DIELECTRIC CHANNELS

The interaction between fast ions and the wall of a dielectric channel charged by randomly deposited ions of the flow was studied. It was shown that gradient forces repulsing ions from the wall caused by charge discreteness only arise when taking into consideration correlations in the relative position of the deposited charges.

X-ray diagnostics of grain shapes in nanomaterials

It is demonstrated that an efficient method can be created and used to determine the shape of grains in nanomaterials. This method relies on the discovered correlations between the amplitudes of different Bragg peaks for wideband X rays scattered in the sample on the grain shape.

Polarization bremsstrahlung in a backward direction for medium structure diagnostics

Possibilities to elaborate the new energy dispersive methods of the diagnostics of a medium atomic structure based on the polarization bremsstrahlung from relativistic electrons moving in a sample are analyzed in the paper. The method of radial density of atoms measuring in a weakly ordered medium is proposed in the paper as well as the method of cluster size determination in small grained medium.

X-ray coherent bremsstrahlung by low energy electrons

Abstract A general theory of X-ray coherent bremsstrahlung by low energy electrons moving in a crystal is developed. The main part of the obtained results is presented in an analytical form. The peculiarity of the emitted photon spectral distribution observed experimentally is explained within the framework of the developed approach. The possibility to create a high efficiency tunable source of quasimonochromatic X-ray is considered.

Polarization bremsstrahlung from relativistic electrons for medium structure diagnostics

Collective effects in the polarization bremsstrahlung from relativistic electrons moving through media ordered in part are considered theoretically and experimentally. The connection of emission spectral-angular characteristics with atomic structures of such targets as polycrystals with accidentally oriented microcrystals and textured polycrystals are elucidated in the work. Results of experimental search of polarization bremsstrahlung from 7MeV electrons crossing polycrystalline targets of Al, Cu and Ni are discussed. Comparison of measured data with theoretical predictions has shown a good agreement for positions and intensities of observed coherent peaks.

Modeling of guiding of 10 keV electron beam by planar dielectric surface

Study of 10 keV electron beam reflection from a single planar dielectric surface was made. Guiding effect for some part of the beam was observed within grazing angles of incidence. Ionization, electron emission and drain of the surface charge were considered in the computer model to explain the results.