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The method of collision spectroscopy, which is based on precision measurement of the kinetic energy of projectile ions after the electron capture process, is used to measure the partial cross sections of the formation of He+(n) ions in specific electronic states upon the capture of an electron by 3He2+ ions with energy E = 1.4–10 keV/a.m.u. from hydrogen atoms. A target of atomic hydrogen with a dissociation degree of 78% was created at the temperature of a tungsten dissociation cell of 2180 K.

The absolute cross sections of single-electron capture and single-electron capture with dissociation in the interaction between incident He2+, C2+, N2+, and O2+ ions with energies from 6.4 to 36.4 keV and СО molecules were measured. It is demonstrated that the cross section of dissociative capture is much larger than the cross section of single-electron capture for O2+ projectile ions. A qualitative explanation for this effect is provided.

The method of “multistop” time-of-flight mass spectrometry has been used to study the mechanism of radiation damage to glycine molecules in the gas phase upon their interaction with He2+ ions with energy E p = 4 keV/amu. The relative cross sections of various elementary processes occurring in single collisions of glycine molecules with the ions were measured for the first time. A difference was found between the fragmentations of intermediate doubly charged ions formed in capture of a single electron with ionization and in two-electron capture, which is accounted for by the difference between the excitation energies of molecular ions.

The relative cross sections of elementary processes occurring in single collisions of tryptophan molecules in the gaseous phase with He2+ ions with energy 4 keV/u are measured using time-of-flight mass spectrometry for studying the mechanism of radiation damage of amino acid molecules. The fragmentation channels for intermediate singly and doubly charged tryptophan molecular ions formed during one-electron capture, two-electron capture, and electron capture with ionization are investigated. Significant difference is observed in the mass spectra of fragmentation of intermediate doubly charged ions formed during the capture with ionization and double capture, which is associated with different energies of excitation of {C11H12N2O2}2+* ions.

Computer simulation is carried out for selecting a compact electron-optical system of the channel for detecting secondary electrons formed during the interaction of xenon atoms or ions with energy of 1-30 keV with Xe atoms. The solid angle of passage of secondary electron beams in a wide range of their initial energies is calculated. The energy spectrum of secondary electrons with various energies is determined by constructing their deceleration curve.

Fragmentation of isolated molecular ions of dipeptides produced by alpha-particles was studied by an experimental technique based on time-of-flight analysis of the charge and mass composition of the fragment ions. The study has shown that the N-Glycylglycine sublimation results in the molecule decomposition into cyclo(GlycylGlycyl) and H2O molecule. We have examined a mass-spectrum of the fragments arising in the cyclo(GlycylGlycyl) interaction with α-particles. By analyzing the temperature dependence of the cyclo(GlycylGlycyl) vapor pressure, we have determined sublimation enthalpy ΔHsubl(453K) = (213 ± 9) kJ/mol.

The possibility of making a local growth class scale for Scots pine based on the data on the growth of separate trunks with peak heights is explored. Two criteria of classifying forest stands according to their growth are considered: (1) according to the parameters of the Mitscherlich function, i.e., b1 (upper limit), b2 (slope), and b3 (shape), and (2) according to the bend point of the tree elongation curve (hm is the height at the time of the peak apical growth, and tm is the age when the peak growth is achieved).

Resonance enhancement of the quantum yield of polarized electrons from photocathodes based on strained short-period semiconductor superlattices is studied. The superlattice is a constituent of a Fabry-Perot optical cavity formed by the outer surface of the photocathode and the distributed Bragg reflector. An increase in the quantum yield by an order of magnitude is observed in the wavelength region corresponding to the maximum degree of polarization of photoemission.

Photoemission of polarized electrons from heterostructures based on InAlGaAs/GaAs superlattices with minimum conduction-band offsets is investigated. The comparison of the excitation energy dependence of the photoemission polarization degree with the calculated spectra make it possible to determine the polarization losses at different stages of the photoemission. A maximum polarization of P = 91% and a quantum yield of 0.14% are close to the best results obtained for photocathodes on the basis of strained semiconductor superlattices.

We discuss the dynamical connection of long-period and nearly parabolic comets with hypothetical transplutonian planets. The statistics includes 792 comets with periods P > 200 years. The orbital plane of the parent planet can be determined from the observed distribution of the perihelia and poles of cometary orbits. The radius of a planetary orbit can be calculated using the Radzievsky-Tisseran criterion. We calculated the minimum distance of each of the 792 orbits to 11 hypothetical planetary orbits. Testing for the kinematic connection of comets with transplutonian planets yielded a negative result. The presence of the nodes of cometary orbits in the transplutonian region is shown to be the result of a geometric effect. We found a high concentration of the nodes and perihelia of cometary orbits in the zone of the terrestrial planets.

Landsat data were used to examine the effect of large-scale insect outbreaks in the forests of southern Siberia. Two insect outbreaks were studied: Ket‐Chulym, ~1.5 million hectares of forest damaged between 1954 and 1957; and Priangar'e, ~0.5‐0.7 million hectares of forest damaged between 1994 and 1996. Landsat scenes from 1980 to 2000 were analyzed. The optimal Landsat channels combination for detecting damage classes were bands 2 (0.525‐0.605 μm), 4 (0.750‐0.900 μm), 5 (1.55‐1.75 μm), and 6 (10.40‐12.50 μm). The damage to the forests caused an increase in radiometric temperature (20.20 ± 0.04°C for damaged forests versus 19.47 ± 0.02°C for healthy forests). The following pattern of forest succession was observed in the outbreak areas: dead stands with dense grass and shrub communities, burn scars, grass and shrub formations, open woodlands, closed young and middle-age birch stands, mature birch stands, and mixed conifer‐deciduous stands. Forest regeneration goes through long-term species-change success...

Resonance enhancement of the quantum efficiency of new polarized electron photocathodes based on a short‐period strained superlattice structures is reported. The superlattice is a part of an integrated Fabry‐Perot optical cavity. We demonstrate that the Fabry‐Perot resonator enhances the quantum efficiency by the order of magnitude in the wavelength region of the main polarization maximum. The high structural quality implied by these results points to the very promising application of these photocathodes for spin‐polarized electron sources.

Optimized AlInGaAs/AlGaAs superlattice with strained quantum wells has been developed, fabricated and studied. The choice of hetero‐layer composition and thicknesses is based on calculations of Sl’s band energy spectrum, photoabsorption spectrum and transport properties. Electron emission from the developed photocathodes demonstrates maximal polarization above 90%.

Resonance enhancement of the quantum efficiency of new polarized electron photocathodes based on a short‐period strained superlattice structures is reported. The superlattice is a part of an integrated Fabry‐Perot optical cavity. We demonstrate that the Fabry‐Perot resonator enhances the quantum efficiency by the order of magnitude in the wavelength region of the main polarization maximum. The high structural quality implied by these results points to the very promising application of these photocathodes for spin‐polarized electron sources.

Photoemission of polarized electrons from heterostructures based on InAlGaAs/GaAs superlattices with minimum conduction‐band offsets is investigated. The comparison of the excitation energy dependence of the photoemission polarization degree with the calculated spectra makes it possible to determine the polarization losses at different stages of the photoemission. A maximum polarization of P = 91% and a quantum efficiency of QE=0.5% are close to the best results obtained for photocathodes that are based on strained semiconductor superlattices.