Analytical-numerical methods of calculations of energy and three-dimensional particle distributions in electromagnetic cascades

Analytical and numerical methods of calculation of the energy and three dimensional EPS characteristics are reported. The angular and lateral functions of electrons in EPS have been obtained by the Landau and small angle approximations A and B and compared with earlier data. A numerical method of solution of cascade equations for the EPS distribution function moments has been constructed. Considering the equilibrium rms angle as an example, errors appearing when approximating the elementary process cross sections by their asymptotic expressions are analyzed

Фізико-механічні характеристики нанокомпозційниих матеріалів на основі фторопласту

In this work, the elastic and strength properties of polymer composites with a polytrifluorochlorethylene matrix and a thermally expanded graphite filler were evaluated by the nanoindentation method, and the effect of the dispersion and concentration of the filler on the mechanical characteristics of nanocomposite materials was considered. It is shown that the microhardness of nanocomposite materials decreases with increasing filler concentration. An increase in the microhardness and Young's modulus with the growth of filler particles was observed for nanocomposite materials with a filler concentration of 3 vol.%. As for nanocomposite materials with a filler volume fraction of 10 vol.%, similar behavior of the mechanical characteristics was observed with an increase in the dispersion of thermally expanded graphite particles to 180 μm. A subsequent increase in the average particle size of thermally expanded graphite leads to a decrease in Young's modulus and microhardness of composites, which may be associated with different degrees of polymer structuring and the formation of different orientational orders from the filler. The observed changes in Young's modulus and H/E ratio indicate a change in the amorphous crystalline behavior of the composite to that characteristic of fine-crystalline materials and depends on the dispersion of thermally expanded graphite. Pages of the article in the issue: 107 - 110 Language of the article: UkrainianУ даній роботі методом наноіндентування було проведено оцінку пружних і міцнісних властивостей полімерних композитів з політрифторхлоретиленовою матрицею і наповнювачем з термічно розширеного графіту. Розглянуто вплив дисперсності і концентрації наповнювача на механічні характеристики нанокомпозиційних матеріалів. Показано, що мікротвердість нанокомпозиційних матеріалів зменшується зі збільшенням концентрації наповнювача. Спостережувані при цьому зміни модуля Юнга і співвідношення H/E свідчать про зміну аморфно кристалічної поведінки композиту до такої, що характерна дрібнокристалічним матеріалам в залежності від дисперсності розширеного графіту

Anatomy of Isolated Monopole in Abelian Projection of SU(2) Lattice Gauge Theory

We study the structure of the isolated static monopoles in the maximal Abelian projection of SU(2) lattice gluodynamics. Our estimation of the monopole radius is $\approx 0.06 fm$.Comment: 4 pages, LaTeX2e, 1 figure (epsfig

Results of investigation of muon fluxes of superhigh energy cosmic rays with X-ray emulsion chambers

The overall data from the investigation of the cosmic ray muon flux in the range of zenith angles (0-90) deg within the energy range (3.5 to 5.0) TeV is presented. The exposure of large X-ray emulsion chambers underground was 1200 tons. year. The data were processe using the method which was applied in the experiment Pamir and differred from the earlier applied one. The obtained value of a slope power index of the differential energy spectrum of the global muon flux is =3.7 that corresponds to the slope of the pion generation differential spectrum, gamma sub PI = 2.75 + or - .04. The analysis of the muon zenith-angular distribution showed that the contribution of rapid generation muons in the total muon flux agree the best with the value .2% and less with .7% at a 90% reliability level

On the relevance of center vortices to QCD

In a numerical experiment, we remove center vortices from an ensemble of lattice SU(2) gauge configurations. This removal adds short-range disorder. Nevertheless, we observe long-range order in the modified ensemble: confinement is lost and chiral symmetry is restored (together with trivial topology), proving that center vortices are responsible for both phenomena. As for the Abelian monopoles, they survive but their percolation properties are lost.Comment: 4 pages, 5 figures; discussion expanded, text compressed... to appear in Phys. Rev. Let

Shape of primary proton spectrum in multi-TeV region from data on vertical muon flux

It is shown, that primary proton spectrum, reconstructed from sea-level and underground data on muon spectrum with the use of QGSJET 01, QGSJET II, NEXUS 3.97 and SIBYLL 2.1 interaction models, demonstrates not only model-dependent intensity, but also model-dependent form. For correct reproduction of muon spectrum shape primary proton flux should have non-constant power index for all considered models, except SIBYLL 2.1, with break at energies around 10-15 TeV and value of exponent before break close to that obtained in ATIC-2 experiment. To validate presence of this break understanding of inclusive spectra behavior in fragmentation region in p-air collisions should be improved, but we show, that it is impossible to do on the basis of the existing experimental data on primary nuclei, atmospheric muon and hadron fluxes.Comment: Submitted to Phys. Rev.

Temperature Dependence of Extended and Fractional SU(3) Monopole Currents

We examine in pure SU(3) the dependence of extended monopole current k and cross-species extended monopole current k^{cross} on temperature t, monopole size L, and fractional monopole charge 1/q. We find that features of both k and k^{cross} are sensitive to t for a range of L and q. In particular, the spatial-temporal asymmetry ratios of both k and k^{cross} are sensitive over a range of L and q to the SU(3) deconfinement transition. The motivation for studying cross, extended, and fractional monopoles in SU(3) is given.Comment: 15 pages (archiving final publication version; very minor revisions

Blocking from continuum and monopoles in gluodynamics

We review the method of blocking of topological defects from continuum used as a non--perturbative tool to construct effective actions for these defects. The actions are formulated in the continuum limit while the couplings of these actions can be derived from simple observables calculated numerically on lattices with a finite lattice spacing. We demonstrate the success of the method in deriving the effective actions for Abelian monopoles in the pure SU(2) gauge models in an Abelian gauge. In particular, we discuss the gluodynamics in three and four space--time dimensions at zero and non--zero temperatures. Besides the action the quantities of our interest are the monopole density, the magnetic Debye mass and the monopole condensate.Comment: 24 pages, 16 figures, RevTeX 4; To be published in Phys. Atom. Nucl. dedicated to the 70th Birthday of Professor Yu. A. Simono

London relation and fluxoid quantization for monopole currents in U(1) lattice gauge theory

We explore the analogy between quark confinement and the Meissner effect in superconductors. We measure the response of color-magnetic "supercurrents" from Dirac magnetic monopoles to the presence of a static quark-antiquark pair in four dimensional U(1) lattice gauge theory. Our results indicate that in the confined phase these currents screen the color-electric flux due to the quarks in an electric analogy of the Meisner effect. We show that U(1) lattice guage theory obeys both a dual London equation and an electric fluxoid quantization condition.Comment: LSUHEP-1-92 May 1992, 13 page

Monopole clusters, Z(2) vortices and confinement in SU(2)

We extend our previous study of magnetic monopole currents in the maximally Abelian gauge [hep-lat/9712003] to larger lattices at small lattice spacings (20^4 at beta = 2.5 and 32^4 at beta = 2.5115). We confirm that at these weak couplings there continues to be one monopole cluster that is very much longer than the rest and that the string tension, K, is entirely due to it. The remaining clusters are compact objects whose population as a function of radius follows a power law that deviates from the scale invariant form, but much too weakly to suggest a link with the analytically calculable size distribution of small instantons. We also search for traces of Z(2) vortices in the Abelian projected fields; either as closed loops of `magnetic' flux or through appropriate correlations amongst the monopoles. We find, by direct calculation, that there is no confining condensate of such flux loops. We also find, through the calculation of doubly charged Wilson loops within the monopole fields, that there is no suppression of the q=2 effective string tension out to at distances of at least r ~ 1.6/sqrt{K}, suggesting that if there are any vortices they are not encoded in the monopole fields.Comment: 26 pages of LaTeX and PostScript figure