A statistical study of the kinetics of phase separation for a liquid crystalline mixture

The kinetics of cholesteric phase growth during the phase separation of an isotropic liquid crystalline mixture was studied by polarizing optical microscopy within the framework of the thermodynamics of irreversible processes. The rules governing time-dependent changes in the parameters of the statistical droplet size distribution of the cholesteric phase were determined. The influence of the thickness of the liquid crystalline mixture layer on the size of the droplets formed was studied.     

Collimator-size effect on the parametric-radiation spectrum

It is shown that, by varying the angular size of a collimator, the spectral distribution of parametric x-ray radiation can be split into two isolated peaks and that the center of the spectral distribution of this radiation is shifted in frequency in response to an increase in the collimator size. It is also predicted that an increase in the angular size of the collimator will lead to a substantial modification of the character of the orientation dependence of the radiation spectrum.     

Generation of circularly polarized photons by relativistic electrons moving in a crystal

The relativistic-electron (relativistic-positron) acceleration arising in its scattering on the potential of a crystal atomic string is highly anisotropic, which causes polarization of accompanying radiation. The possibility of developing an efficient source of circularly polarized photons by using electrons or positrons of energies attainable at many operating accelerators is demonstrated and analyzed.     

Modification of the EDXD method for diagnostics of polycrystalline and fine-grained media

The possibilities of using broadband X rays for diagnostics of the atomic structure of solids are considered. It is proposed to use virtual photons of the Coulomb field of a relativistic electron beam as primary probe radiation.     

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.     

Defining the distribution function of mosaic crystal grains on orientation angles using synchrotron radiation

A new method of measuring the angular distribution function of grains in mosaic crystals is proposed and studied.     

Feature of kinematic diffraction of nonmonochromatic divergent X-ray beams in a crystal with a periodically strained lattice

Coherent scattering of a nonmonochromatic divergent beam of X-ray quanta in a crystal excited by an acoustic wave is described using a kinematic approach. The possibility of manifestation of a peculiar effect of amplification of the diffracted X-ray beam by the acoustic wave is predicted using this approach.