21 research outputs found
Backward scattering of low-energy antiprotons by highly charged and neutral uranium: Coulomb glory
Collisions of antiprotons with He-, Ne-, Ni-like, bare, and neutral uranium
are studied theoretically for scattering angles close to 180 and
antiproton energies with the interval 100 eV -- 10 keV. We investigate the
Coulomb glory effect which is caused by a screening of the Coulomb potential of
the nucleus and results in a prominent maximum of the differential cross
section in the backward direction at some energies of the incident particle. We
found that for larger numbers of electrons in the ion the effect becomes more
pronounced and shifts to higher energies of the antiproton. On the other hand,
a maximum of the differential cross section in the backward direction can also
be found in the scattering of antiprotons on a bare uranium nucleus. The latter
case can be regarded as a manifestation of the screening property of the
vacuum-polarization potential in non-relativistic collisions of heavy
particles.Comment: 14 pages, 5 figure
Nucleon-nucleon interaction in the -matrix inverse scattering approach and few-nucleon systems
The nucleon-nucleon interaction is constructed by means of the -matrix
version of inverse scattering theory. Ambiguities of the interaction are
eliminated by postulating tridiagonal and quasi-tridiagonal forms of the
potential matrix in the oscillator basis in uncoupled and coupled waves,
respectively. The obtained interaction is very accurate in reproducing the
scattering data and deuteron properties. The interaction is used in the no-core
shell model calculations of H and He nuclei. The resulting binding
energies of H and He are very close to experimental values.Comment: Text is revised, new figures and references adde
Algebraic Model for scattering in three-s-cluster systems. I. Theoretical Background
A framework to calculate two-particle matrix elements for fully
antisymmetrized three-cluster configurations is presented. The theory is
developed for a scattering situation described in terms of the Algebraic Model.
This means that the nuclear many-particle state and its asymptotic behaviour
are expanded in terms of oscillator states of the intra-cluster coordinates.
The Generating Function technique is used to optimize the calculation of matrix
elements. In order to derive the dynamical equations, a multichannel version of
the Algebraic Model is presented.Comment: 20 pages, 1 postscript figure, submitted to Phys. Rev.
Ionospheric gas dynamics of satellites and diagnostic probes
The gas dynamics of interactions of a tenuous ionosphere with moving satellites and probes that have bearings on the diagnostics of the ionosphere are discussed. Emphasis is on the cases where the body is moving at mesothermal speeds, namely intermediate between the thermal speeds of ions and electrons of the ambient ionosphere. Methods of collision-free plasma kinetics with self-consistent field are used. The development of the topics for discussion starts with stationary Langmuir probe which entails the basic mechanism of body-plasma interaction that becomes further intricated as the body moves at a higher and higher speed. Applications of the theory of plasma interaction to meteors which move in the ionosphere are also presented.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43801/1/11214_2004_Article_BF00212707.pd
Forestry of Lisino as the unique testing area for the soil and ecologic monitoring
Forestry of Lisino is the perspective area for the organization and conduction of soil and ecologic monitoring. It is characterized by ecosystems, typical for the North-West, which are least altered by anthropogenic impact. Also it is characterized by the availability of long-term investigation materials of soils and soil cover, and the availability of soil monoliths collected at different years. A. A. Rode made a substantial contribution in the investigation of soils and soil cover of forestry of Lisino. The changes of typomorphic characteristics were determined and the analysis of taxonomic structure of microbiome was conducted for the soddy-podzolic soil developed on driftless clay loam. On the basis of comparative analysis of actual samples from the soddy-podzolic soils and the samples from soil monoliths, it was set that the significant pH decrease occurred during the 75 years, and the degree of base saturation also decreased significantly. The monitoring polygons are lain along the II International Soil Scientists Congress route held in 1930. The separation of seven objects of soil and ecologic monitoring is substantiated, as they characterize all ecosystems typical for Lisin forestry. The soils of the four objects of monitoring are included in the Red Book of soils of Leningrad oblast: the soddy-podzolic soil developed on the moraine loams - âthe Pit of Rodeâ, the soddy elluvial metamorphic developed on varved clays - âKostenkiâ, the peat humic gleyzem oxidative gley - âSulandaâ and alluvial gray humic soil - âLustovkaâ
Scattering of conduction electrons by impurities in quantizing magnetic fields and calculation of electrical conductivity
Coulomb glory in low-energy antiproton scattering by a heavy nucleus: screening effect of vacuum polarization
Structure, Energy, and Vibrational Frequencies of Oxygen Allotropes On (n †6) in the Covalently Bound and van der Waals Forms: Ab Initio Study at the CCSD(T) Level
Recent experiments on the UV and electron beam irradiation of solid O2 reveals a series of IR features near
the valence antisymmetric vibration band of O3 which are frequently interpreted as the formation of unusual On allotropes in the forms of weak complexes or covalently bound molecules. In order to elucidate the question of the nature of the irradiation products, the structure, relative energies, and vibrational
frequencies of various forms of On (n = 1â6) in the singlet, triplet, and, in some cases, quintet states were studied using the CCSD(T) method up to the CCSD(T,full)/cc-pCVTZ and CCSD(T,FC)/aug-cc-pVTZ levels. The results of calculations demonstrate the existence of stable highly symmetric structures O4(D3h), O4 (D2d), and O6 (D3d) as well as the intermolecular complexes O2·O2, O2·O3, and O3·O3 in different conformations. The
calculations show that the local minimum corresponding to the O3···O complex is quite shallow and cannot explain the Îœ3 band features close to 1040 cmâ1, as was proposed previously. For the ozone dimer, a new conformer was found which is more stable than the structure known to date. The effect of the ozone dimer on the registered IR spectra is discussed