962 research outputs found
The model of particle production by strong external sources
Using some knowledge of multiplicity disributions for high energy reactions,
it is possible to propose a simple analytical model of particle production by
strong external sources. The model describes qualitatively most peculiar
properties of the distributions. The generating function of the distribution
varies so drastically as it can happen at phase transitions.Comment: 7 pages, no Figures, LATEX; Eq. (10) corrected, Eqs (25), (26) added,
ref [20] corrected; Pisma v Zhetf 84, n5 (2006
Assessment and Calculation of Groundwater Reserves for Drinking Water Supply in Mountainous Areas of the Chechen Republic
This article is devoted to the urgent problem of drinking water supply in the mountainous regions of the Chechen Republic. The results of the assessment and calculation of groundwater reserves are presented. The article gives a brief assessment of the hydrogeological conditions of the study area, especially the complex of alluvial lower-upper Pleistocene sediments of the overdeepened river valleys, represented by boulder-pebble and boulder-rubbly formations with sand and sand-loamy aggregates. For inventory assessment and choice of a methodology of the reserves calculation in the Research Methods section, the hydrogeological conditions for the formation of groundwater are schematized in all the four study areas (Khimoyskiy, Shatoyskiy, Itum-Kalinskiy, Vedenskiy). On the basis of experimental field hydrogeological works, the calculation hydrogeological parameters necessary for the calculation of the groundwater reserves are determined (the main hydrogeological parameters on the estimated areas are given in the article, in the table 1). In the Methods section, the detailed justification of the scheme of placement of project wells is given (further the wells are supposed to be used as a water intake). For all the four areas – Khimoyskiy, Shatoyskiy, Itum-Kalinskiy and Vedenskiy the “strip aquifer” scheme is adopted as the calculation, limited by two parallel impermeable contours (the slopes of river valleys are composed of impermeable water-resistant bedrocks). In the Results section, all schemes, formulas and brief characteristics of each investigated area (the acreage, the necessary water demand, the type of project water intake) are given. For each area, an security assessment of the calculated reserves is given, which is confirmed by the balance method (all the calculations are given in the article). In conclusion of the article in table 03 the data on the reserves of fresh groundwater based on the results of prospecting-evaluation works of 01.06.2015 are given
Interplay of inequivalent atomic positions in resonant x-ray diffraction of Fe3BO6
'Forbidden' Bragg reflections of iron orthoborate Fe3BO6 were studied
theoretically and experimentally in the vicinity of the iron K edge. Their
energy spectra are explained as resulting from the interference of x-rays
scattered from two inequivalent crystallographic sites occupied by iron ions.
This particular structure property gives rise to complex azimuthal dependences
of the reflection intensities in the pre-edge region as they result from the
interplay of site specific dipole-quadrupole and quadrupole-quadrupole resonant
scattering. Also evidenced is an isotropic character of the absorption
spectrum. Self-absorption correction to the diffraction data, as well as
possible contributions of thermal vibrations and magnetic order, are discussed.
Particular care is given to extracting clean spectra from the data, and it is
demonstrated that excellent results can be obtained even from measurements that
appear corrupted by several effects such as poor crystal quality and multiple
scattering.Comment: 12 page
Modified Dispersion Relations from the Renormalization Group of Gravity
We show that the running of gravitational couplings, together with a suitable
identification of the renormalization group scale can give rise to modified
dispersion relations for massive particles. This result seems to be compatible
with both the frameworks of effective field theory with Lorentz invariance
violation and deformed special relativity. The phenomenological consequences
depend on which of the frameworks is assumed. We discuss the nature and
strength of the available constraints for both cases and show that in the case
of Lorentz invariance violation, the theory would be strongly constrained.Comment: revtex4, 9 pages, updated to match published versio
Fragmentation of relativistic nuclei in peripheral interactions in nuclear track emulsion
The technique of nuclear track emulsions is used to explore the fragmentation
of light relativistic nuclei down to the most peripheral interactions - nuclear
"white" stars. A complete pattern of therelativistic dissociation of a B
nucleus with target fragment accompaniment is presented. Relativistic
dissociation Be is explored using significant statistics and
a relative contribution of Be decays from 0 and 2 states is
established. Target fragment accompaniments are shown for relativistic
fragmentation N3He+H and Ne5He. The leading role of the
electromagnetic dissociation on heavy nuclei with respect to break-ups on
target protons is demonstrated in all these cases. It is possible to conclude
that the peripheral dissociation of relativistic nuclei in nuclear track
emulsion is a unique tool to study many-body systems composed of lightest
nuclei and nucleons in the energy scale relevant for nuclear astrophysics.Comment: 15 pages, 4 figures, 4 tables, conference: Relativistic nuclear
physics: from Nuclotron to LHC energies, Kiev, June 18-22, 200
Clustering in light nuclei in fragmentation above 1 A GeV
The relativistic invariant approach is applied to analyzing the 3.3 A GeV
Ne fragmentation in a nuclear track emulsion. New results on few-body
dissociations have been obtained from the emulsion exposures to 2.1 A GeV
N and 1.2 A GeV Be nuclei. It can be asserted that the use of the
invariant approach is an effective means of obtaining conclusions about the
behavior of systems involving a few He nuclei at a relative energy close to 1
MeV per nucleon. The first observations of fragmentation of 1.2 A GeV B
and C nuclei in emulsion are described. The presented results allow one
to justify the development of few-body aspects of nuclear astrophysics.Comment: 7 pages, 8 figures, 3 tables, Nuclear Physics in Astrophysics-2,
16-20 May, 2005 (ATOMKI), Debrecen, Hungar
QCD and models on multiplicities in and interactions
A brief survey of theoretical approaches to description of multiplicity
distributions in high energy processes is given. It is argued that the
multicomponent nature of these processes leads to some peculiar characteristics
observed experimentally. Predictions for LHC energies are presented. It is
shown that similarity of the energy dependence of average multiplicities in
different reactions is not enough alone to suggest the universal mechanism of
particle production in strongly-interacting systems. Other characteristics of
multiplicity distributions depend on the nature of colliding partners.Comment: 16 pages, 11 figures, Phys. Atom. Nuc
Adiabatic description of nonspherical quantum dot models
Within the effective mass approximation an adiabatic description of
spheroidal and dumbbell quantum dot models in the regime of strong dimensional
quantization is presented using the expansion of the wave function in
appropriate sets of single-parameter basis functions. The comparison is given
and the peculiarities are considered for spectral and optical characteristics
of the models with axially symmetric confining potentials depending on their
geometric size making use of the total sets of exact and adiabatic quantum
numbers in appropriate analytic approximations
Topology of "white" stars in relativistic fragmentation of light nuclei
In the present paper, experimental observations of the multifragmentation
processes of light relativistic nuclei carried out by means of emulsions are
reviewed. Events of the type of "white" stars in which the dissociation of
relativistic nuclei is not accompanied by the production of mesons and the
target-nucleus fragments are considered.
A distinctive feature of the charge topology in the dissociation of the Ne,
Mg, Si, and S nuclei is an almost total suppression of the binary splitting of
nuclei to fragments with charges higher than 2. The growth of the nuclear
fragmentation degree is revealed in an increase in the multiplicity of singly
and doubly charged fragments with decreasing charge of the non-excited part of
the fragmenting nucleus.
The processes of dissociation of stable Li, Be, B, C, N, and O isotopes to
charged fragments were used to study special features of the formation of
systems consisting of the lightest , d, and t nuclei. Clustering in
form of the He nucleus can be detected in "white" stars via the
dissociation of neutron-deficient Be, B, C, and N isotopes.Comment: 20 pages, 3 figures, 9 tables, conference: Conference on Physics of
Fundamental Interactions, Moscow, Russia, 1-5 Mar 2004.(Author's translation
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