Karpov S.A.,Dukhov All Russia Research Institute of Automatics |
Potapenko I.F.,RAS Keldysh Institute of Applied Mathematics
Plasma Physics Reports | Year: 2015
A stochastic method of simulation of Coulomb interaction is considered. The main idea of the method is to approximate the nonlinear Landau kinetic collision integral by the Boltzmann integral. In its realization, the method can be attributed to a wide class of Monte Carlo-type methods. It is easily combined with the existing particle methods used to simulate collisionless plasmas. This is important for simulation of the dynamics of both laboratory and space plasmas when the mean free path of plasma particles is comparable with the plasma inhomogeneity scale length. Illustrative examples of relaxation of two-temperature plasma being subject to a high-frequency alternating electric field are given, and differences from their classical description are considered. The method satisfies the conservation laws for the number of particles, momentum, and energy and is simple and efficient in implementation. © 2015, Pleiades Publishing, Ltd.
Didenko A.N.,National Research Nuclear University |
Shikanov A.E.,National Research Nuclear University |
Rashchikov V.I.,National Research Nuclear University |
Ryzhkov V.I.,Dukhov All Russia Research Institute of Automatics |
Shatokhin V.L.,National Research Nuclear University
Technical Physics | Year: 2014
The generation of neutron pulses with a duration of 1-100 ns using small vacuum accelerating tubes is considered. Two physical models of acceleration of short deuteron bunches in pulse neutron generators are described. The dependences of an instantaneous neutron flux in accelerating tubes on the parameters of pulse neutron generators are obtained using computer simulation. The results of experimental investigation of short-pulse neutron generators based on the accelerating tube with a vacuum-arc deuteron source, connected in the circuit with a discharge peaker, and an accelerating tube with a laser deuteron source, connected according to the Arkad'ev-Marx circuit, are given. In the experiments, the neutron yield per pulse reached 107 for a pulse duration of 10-100 ns. The resultant experimental data are in satisfactory agreement with the results of computer simulation. © 2014 Pleiades Publishing, Ltd.
Simutin A.S.,Dukhov All Russia Research Institute of Automatics |
Chernov M.Y.,Dukhov All Russia Research Institute of Automatics |
Gasanov A.A.,OAO Giredmet |
Orlov A.D.,RAS Institute of Solid State Physics |
And 2 more authors.
Instruments and Experimental Techniques | Year: 2013
Results of investigations of the scintillation detector based on a LaBr3:Ce crystal and a ΦCyrillic capital letter EY-184 photomultiplier tube are presented. It is shown that, optimizing the ΦCyrillic capital letter EY-184 photomultiplier tube circuit by reading out the signal from the next to last dynode, it is possible to utilize the spectrometric properties of the LaBr3:Ce crystal. © 2013 Pleiades Publishing, Inc.
Ashitkov S.I.,RAS Joint Institute for High Temperatures |
Komarov P.S.,RAS Joint Institute for High Temperatures |
Ovchinnikov A.V.,RAS Joint Institute for High Temperatures |
Struleva E.V.,RAS Joint Institute for High Temperatures |
And 3 more authors.
Quantum Electronics | Year: 2014
Using an interferometric continuous monitoring technique, we have investigated the motion of the surface of an aluminium target in the case of femtosecond laser ablation at picosecond time delays relative to the instant of laser exposure. Measurements of the temporal target dispersion dynamics, molecular dynamics simulation results and the morphology of the ablation crater have demonstrated a thermomechanical (spall) nature of the disruption of the condensed phase due to the cavitation-driven formation and growth of vapour phase nuclei upon melt expansion, followed by the formation of surface nanostructures upon melt solidification. The tensile strength of heated aluminium in a condensed state has been determined experimentally at an expansion rate of ∼109 s-1. © 2014 Kvantovaya Elektronika and Turpion Ltd.
Inogamov N.A.,Russian Academy of Sciences |
Zhakhovskii V.V.,Dukhov All Russia Research Institute of Automatics |
Khokhlov V.A.,Russian Academy of Sciences
Journal of Experimental and Theoretical Physics | Year: 2015
It is well known that during ablation by an ultrashort laser pulse, the main contribution to ablation of the substance is determined not by evaporation, but by the thermomechanical spallation of the substance. For identical metals and pulse parameters, the type of spallation is determined by film thickness df. An important gauge is metal heating depth dT at the two-temperature stage, at which electron temperature is higher than ion temperature. We compare cases with df < dT (thin film) and df ≫ dT (bulk target). Radius RL of the spot of heating by an optical laser is the next (after df) important geometrical parameter. The morphology of film bulging in cases where df < dT on the substrate (blistering) changes upon a change in radius RL in the range from diffraction limit RL ∼ λ to high values of RL ≫ λ, where λ ∼ 1 μm is the wavelength of optical laser radiation. When df < dT, RL ∼ λ, and Fabs > Fm, gold film deposited on the glass target acquires a cupola-shaped blister with a miniature frozen nanojet in the form of a tip on the circular top of the cupola (Fabs and Fm are the absorbed energy and the melting threshold of the film per unit surface area of the film). A new physical mechanism leading to the formation of the nanojet is proposed. © 2015, Pleiades Publishing, Inc.
Kosov M.V.,Dukhov All Russia Research Institute of Automatics |
Chertkov A.V.,Skolkovo Institute of Science and Technology
Instruments and Experimental Techniques | Year: 2015
A numerical analysis of the confidence of detecting a significant deviation from the background distribution according to the Neumann-Pirson for random quantities, which obey the Poisson criterion, was performed. Relationships are established between such quantities as the signal-to-background ratio, the expected mean background value, the detection threshold, and the detection confidence. To completely define the problem, it is sufficient to know two of these four parameters. Because the distribution of events in each bin of a histogram at unit weights of events obey the Poisson distribution law, the obtained mutual dependences of variables are of fundamental importance and can be used in searches for a deviation from predictions of standard models or for a desired-signal detection against a background of known background distributions. The determined confidence values comply with the values that were obtained using the χ2 method (Pirson criterion). © 2015, Pleiades Publishing, Inc.
Romodanov V.L.,National Research Nuclear University MEPhI |
Sakharov V.K.,National Research Nuclear University MEPhI |
Chernikova D.N.,National Research Nuclear University MEPhI |
Ryzhkov V.I.,Dukhov All Russia Research Institute of Automatics |
And 2 more authors.
Atomic Energy | Year: 2011
The results of computational studies of the effect of the building materials used in ING-031, -06 pulsed neutron generators, produced by the Dukhov All-Russia Research Institute of Automatics, on the properties of the neutron and photon fields in the air near them are presented. The studies showed that in the real structures of the generators both the angular and energy distributions of the neutrons and photons change considerably. An isotropic angular distribution of the neutrons emanating from the target becomes anisotropic. Low-energy neutrons, which are not present in a pure target with no structural elements, appear in the energy distribution of the neutrons leaving the surface of the generator. The energy range extends to the thermal region. High-energy photons from inelastic scattering and radiative capture, which are absent in pure targets, appear as a result of the interaction of the neutrons with the structural elements. The building elements in a pulse generator distort the shape of the neutron pulse because of the appearance of moderated neutrons. The regularities found must be taken into account when solving practical problems arising with the use of neutron generators. © 2011 Springer Science+Business Media, Inc.
Asyunin V.I.,Dukhov All Russia Research Institute of Automatics |
Bushin S.A.,Dukhov All Russia Research Institute of Automatics |
Davydov S.G.,Dukhov All Russia Research Institute of Automatics |
Dolgov A.N.,Dukhov All Russia Research Institute of Automatics |
And 4 more authors.
Technical Physics Letters | Year: 2016
Regularities of erosion and transport of the material of discharger elements have been studied by the methods of surface structure visualization and X-ray fluorescence elemental microanalysis. Microrelief and oxide film on the surface of cathode material are found to affect the development of arc discharge in a commutator. © 2016, Pleiades Publishing, Ltd.
Bork L.V.,Institute of Theoretical and Experimental Physics |
Ogarkov S.L.,Dukhov All Russia Research Institute of Automatics
Theoretical and Mathematical Physics | Year: 2014
We study the problem of the condensate (stochastic average) origination for an auxiliary field in the Kardar-Parisi-Zhang equation and its matrix generalization. We cannot reliably conclude that there is a condensate for the Kardar-Parisi-Zhang equation in the framework of the one-loop approximation improved by the renormalization group method. The matrix generalization of the Kardar-Parisi-Zhang equation permits a positive answer to the question of whether there is a nonzero condensate, and the problem can be solved exactly in the large-N limit. © 2014 Pleiades Publishing, Ltd.
Andrianov V.P.,Dukhov All Russia Research Institute of Automatics |
Bandurkin K.V.,Dukhov All Russia Research Institute of Automatics |
Grigor'Ev S.A.,Dukhov All Russia Research Institute of Automatics |
Zakharov A.E.,Dukhov All Russia Research Institute of Automatics |
And 2 more authors.
Instruments and Experimental Techniques | Year: 2010
The instrumental complex described is intended for recording the velocity of motion of the surface of a sample under study exposed to impact-explosion loading in gas-dynamic investigations of properties of structural materials. The velocity is determined from the Doppler wavelength shift of reflected radiation of the probing laser measured by the interferometry method. A solid-state laser with a pulse duration of >50 μs, an average power of at least 50 W, and a system for controlling the resonator quality factor, which ensures radiation stabilization for maintaining an almost rectangular pulse shape, is used as the probing-radiation source. © 2010 Pleiades Publishing, Ltd.