2,727 research outputs found

    Slow oscillations of magnetoresistance in quasi-two-dimensional metals

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    Slow oscillations of the interlayer magnetoresistance observed in the layered organic metal β\beta -(BEDT-TTF)2_2IBr2_2 are shown to originate from the slight warping of its Fermi surface rather than from independent small cyclotron orbits. Unlike the usual Shubnikov-de Haas effect, these oscillations are not affected by the temperature smearing of the Fermi distribution and can therefore become dominant at high enough temperatures. We suggest that the slow oscillations are a general feature of clean quasi-two-dimensional metals and discuss possible applications of the phenomenon.Comment: 11 pages, 3 figure

    The experimental cascade curves of EAS at E sub 0 10(17) eV obtained by the method of detection of Cherenkov pulse shape

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    The individual cascade curves of EAS with E sub 0 10 to the 17th power eV/I to 3/ were studied by detection of EAS Cherenkov light pulses. The scintillators located at the center of the Yakutsk EAS array within a 500-m radius circle were used to select the showers and to determine the main EAS parameters. The individual cascade curves N(t) were obtained using the EAS Cherenkov light pulses satisfying the following requirements: (1) the signal-to-noise ratio fm/delta sub n 15, (2) the EAS axis-detector distance tau sub 350 m, (3) the zenith angle theta 30 deg, (4) the probability for EAS to be detected by scintillators W 0.8. Condition (1) arises from the desire to reduce the amplitude distortion of Cherenkov pulses due to noise and determines the range of EAS sizes, N(t). The resolution times of the Cherenkov pulse shape detectors are tau sub 0 approx. 23 ns which results in distortion of a pulse during the process of the detection. The distortion of pulses due to the finiteness of tau sub 0 value was estimated. It is shown that the rise time of pulse becomes greater as tau sub 0.5/tau sub 0 ratio decreases

    Determination of the dimensions of the heat-affected zone in welding gas pipeline components

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    Analytical decisions supported by experimental data were used to determine the dependences for calculating the size of the heat-affected zone (HAZ) in multilayer welding of circumferential joints in transmission gas pipelines. Data on the dimensions of this zone are essential for evaluating the possibility of applying cold cutting in the rejection of elements of gas pipelines because of defects in circumferential welded joints or welded joints in transition rings in the vicinity of circumferential welded joints. © 2013 Copyright Taylor and Francis Group, LLC

    Lie group analysis for multi-scale plasma dynamics

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    An application of approximate transformation groups to study dynamics of a system with distinct time scales is discussed. The utilization of the Krylov-Bogoliubov-Mitropolsky method of averaging to find solutions of the Lie equations is considered. Physical illustrations from the plasma kinetic theory demonstrate the potentialities of the suggested approach. Several examples of invariant solutions for the system of the Vlasov-Maxwell equations for the two-component (electron-ion) plasma are presented.Comment: Latex, 15 pages, 7 figure. This is an enlarged contribution to Journal of Nonlinear Mathematical Physics v.18, Suppl. 1 (2011) p.163-175 with modest stylistic corrections introduced mainly in the third Sectio

    Surface Crystallization in a Liquid AuSi Alloy

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    X-ray measurements reveal a crystalline monolayer at the surface of the eutectic liquid Au_{82}Si_{18}, at temperatures above the alloy's melting point. Surface-induced atomic layering, the hallmark of liquid metals, is also found below the crystalline monolayer. The layering depth, however, is threefold greater than that of all liquid metals studied to date. The crystallinity of the surface monolayer is notable, considering that AuSi does not form stable bulk crystalline phases at any concentration and temperature and that no crystalline surface phase has been detected thus far in any pure liquid metal or nondilute alloy. These results are discussed in relation to recently suggested models of amorphous alloys.Comment: 12 pages, 3 figures, published in Science (2006

    Documentary films translation: approaches and challenges

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    The article presents a comprehensive overview of different approaches to translating documentary audiovisual productions. The abundance of documentary films available at online platforms lead to a higher demand for their translation into different languages as the modern tradition in viewing audiovisual content online requires a variety of language choice and modes of translation presentation (subtitling, voice-over, accessibility means for people with auditory and visual challenges). Documentary productions present a separate group of films that can be further classified according to their production methods and the presentation styles. The specificity of each item of the detailed classification calls for an individualized approach to handling the process of translating these productions. Film terminology also requires special attention as it is one of the basic challenges of documentary productions translation

    Spin light of neutrino in gravitational fields

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    We predict a new mechanism for the spin light of neutrino (SLνSL\nu) that can be emitted by a neutrino moving in gravitational fields. This effect is studied on the basis of the quasiclassical equation for the neutrino spin evolution in a gravitational field. It is shown that the gravitational field of a rotating object, in the weak-field limit, can be considered as an axial vector external field which induces the neutrino spin procession. The corresponding probability of the neutrino spin oscillations in the gravitational field has been derived for the first time. The considered in this paper SLνSL\nu can be produced in the neutrino spin-flip transitions in gravitational fields. It is shown that the total power of this radiation is proportional to the neutrino gamma factor to the fourth power, and the emitted photon energy, for the case of an ultra relativistic neutrino, could span up to gamma-rays. We investigate the SLνSL\nu caused by both gravitational and electromagnetic fields, also accounting for effects of arbitrary moving and polarized matter, in various astrophysical environments. In particular, we discuss the SLνSL\nu emitted by a neutrino moving in the vicinity of a rotating neutron star, black hole surrounded by dense matter, as well as by a neutrino propagating in the relativistic jet from a quasar.Comment: 14 pages in LaTex with 1 eps figure; derivation of the neutrino spin oscillations probability in gravitational fields and several clarifying notes are added, typos correcte
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