RAS Institute for High Energy Densities

Moscow, Russia

RAS Institute for High Energy Densities

Moscow, Russia
SEARCH FILTERS
Time filter
Source Type

Dzlieva E.S.,Saint Petersburg State University | Karasev V.Yu.,Saint Petersburg State University | Petrov O.F.,RAS Institute for High Energy Densities
Journal of Experimental and Theoretical Physics | Year: 2012

The rotational dynamics of single dust grains in a weak magnetic field is investigated on a kinetic level. Experiments reveal spin-up of spherical dust grains and alignment of their magnetic moments parallel to the magnetic induction vector. The angular velocity of spinning prolate grains varies as magnetic induction increases to 250 G. Spinning dust grains are found to flip over only when the magnetic field magnitude is changing. The results demonstrate that dusty plasma has paramagnetic properties. Qualitative interpretations are proposed to explain newly discovered phenomena. © Pleiades Publishing, Inc., 2012.


Belevtsev A.A.,RAS Institute for High Energy Densities | Kazantsev S.Yu.,RAS A.M. Prokhorov General Physics Institute | Kononov I.G.,RAS A.M. Prokhorov General Physics Institute | Firsov K.N.,RAS A.M. Prokhorov General Physics Institute
Quantum Electronics | Year: 2010

The development of detachment instability in active media of electric-discharge non-chain HF(DF) lasers due to the electron-impact detachment of electrons from negative ions is considered. This instability is initiated in large volumes of SF6-based gas mixtures, spatially separated from electrodes and heated by a pulsed CO2 laser. The self-organisation of self-sustained volume discharge upon laser heating, which results in the formation of quasi-periodic plasma structures within the discharge gap, is experimentally investigated. The evolution of these structures, depending on the gas temperature and specific deposition of electric energy, is analysed. The possible relationship between the self-organisation and detachment instability is discussed. A mechanism of development of single plasma channels in the working media of HF(DF) lasers, based on electron-impact destruction of negative ions is proposed. © 2010 Kvantovaya Elektronika and Turpion Ltd.


Veysman M.,RAS Institute for High Energy Densities | Andreev N.E.,Moscow Institute of Physics and Technology | Cassou K.,University Paris - Sud | Cassou K.,French National Center for Scientific Research | And 6 more authors.
Journal of the Optical Society of America B: Optical Physics | Year: 2010

A non-symmetrical theoretical model is used to describe the propagation of laser beams in dielectric capillary waveguides under non-ideal coupling conditions. The displacement of the laser beam focusing point from the capillary axis, the deviation of the transverse energy distribution from a symmetric one, and an angle of incidence different from zero modify, through the excitation and beating of several modes, the energy repartition during the propagation in the waveguides. The results of modeling are in very good agreement with experimental results, obtained with a low-intensity laser beam on a test bench, where good control of the laser energy distribution in the focal plane, the focusing point position, and the angle of incidence was achieved. © 2010 Optical Society of America.


Liu J.,China Earthquake Administration | Zhang X.,China Earthquake Administration | Novikov V.,RAS Institute for High Energy Densities | Shen X.,Chinese Institute of Crustal Dynamics
Journal of Geophysical Research A: Space Physics | Year: 2016

In recent years, many researchers pay more attention to abnormities before earthquake, and in this study, seismo-ionospheric synchronous disturbances at different altitudes by GPS and satellite observations were first studied around one Sumatra Indonesia Ms 7.2 earthquake that occurred on 5 July 2005. By using the same temporal and spatial methods, data of GPS-total electron content (TEC) from Jet Propulsion Laboratory, electron density (Ne) from Detection of Electro-Magnetic Emissions Transmitted from Earthquake Regions, and ion density (Ni) from Defense Meteorological Satellite Program were deeply analyzed. The ionospheric plasma disturbances in GPS-TEC and increasement of Ne at 710km were found on 4 July, and plasma density at the three altitudes has all increased on 7 July after the earthquake. All the disturbances were not just above the epicenter. TEC perturbations have happened at the east of the epicenter for the two days, and electron density enhancement at 710km has moved to west of the TEC perturbations at the same time on 4 July, which may be caused by E×B drift. The moving direction of upgoing plasma was simulated using SAMI2 model. The results have shown that the plasma will move to higher altitude along the geomagnetic force line, which could exactly account for the plasma density enhancement in the northern direction of the geomagnetic south latitude earthquake. ©2016. American Geophysical Union.


Simonenko E.P.,RAS Kurnakov Institute of General and Inorganic Chemistry | Ignatov N.A.,RAS Kurnakov Institute of General and Inorganic Chemistry | Simonenko N.P.,RAS Kurnakov Institute of General and Inorganic Chemistry | Ezhov Yu.S.,RAS Institute for High Energy Densities | And 2 more authors.
Russian Journal of Inorganic Chemistry | Year: 2011

Nanocrystalline powders of super-refractory complex carbides Ta 4HfC 5 and Ta 4ZrC 5 were synthesized using a hybrid method comprising sol-gel technology for preparing highly dispersed metal oxidescarbon starting mixtures and a relatively low-temperature (1300-1500°C) carbothermal synthesis under a dynamic vacuum (P = 1 × 10 -3 to 1 × 10 -5 MPa). The elemental and phase compositions of the products and average crystallite sizes were determined. TEM was used to study particle morphology and dispersion. Microstructures were observed by SEM. BET specific surface areas were determined for powders prepared at 1400°C. © 2011 Pleiades Publishing, Ltd.


Apfel'baum E.M.,RAS Institute for High Energy Densities | Vorob'ev V.S.,RAS Institute for High Energy Densities
Russian Journal of Mathematical Physics | Year: 2011

It is proved that an ideal Bose gas in a space of fractional dimension presents a quite adequate description of gas states for actual matters and model systems up to the beginning of condensation. © 2011 Pleiades Publishing, Ltd.


Zhdanov S.K.,Max Planck Institute for Extraterrestrial Physics | Schwabe M.,Max Planck Institute for Extraterrestrial Physics | Heidemann R.,Max Planck Institute for Extraterrestrial Physics | Sutterlin R.,Max Planck Institute for Extraterrestrial Physics | And 11 more authors.
New Journal of Physics | Year: 2010

Experimental results on an auto-oscillatory pattern observed in a complex plasma are presented. The experiments are performed with an argon plasma, which is produced under microgravity conditions using a capacitively coupled rf discharge at low power and gas pressure. The observed intense wave activity in the complex plasma cloud correlates well with the low-frequency modulation of the discharge voltage and current and is initiated by periodic void contractions. Particle migrations forced by the waves are of long-range repulsive and attractive character. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.


Belevtsev A.A.,RAS Institute for High Energy Densities | Firsov K.N.,RAS A.M. Prokhorov General Physics Institute | Kazantsev S.Y.,RAS A.M. Prokhorov General Physics Institute | Kononov I.G.,RAS A.M. Prokhorov General Physics Institute | Zhang L.-M.,CAS Changchun Institute of Optics and Fine Mechanics and Physics
Chinese Optics | Year: 2011

This paper reports on investigating the ionization instability in active media of electric discharge non-chain HF(DF) lasers due to electron impact detachment of electrons from negative ions. This instability has been triggered in large volumes of SF6-based mixtures, spatially separated from electrodes, through the gas heating by a pulsed CO2 laser radiation. A self-organization phenomenon in a Self-sustained Volume Discharge(SSVD) on a laser-induced gas heating and resulting in formation of quasi-periodic plasma structures in the bulk of discharge gap is experimentally studied. Special attention is given to the evolution of these structures on changing the gas temperature and specific electric energy depositions. A plausible relation of the found self-organization effect to the electron detachment instability treated is discussed. Also suggested is the mechanism of moving a single plasma channel in working media of HF(DF) lasers owing to destruction of negative ions by electron impact.


Veysman M.,RAS Institute for High Energy Densities | Andreev N.E.,Moscow Institute of Physics and Technology | Maynard G.,University Paris - Sud | Cros B.,University Paris - Sud
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2012

A model describing the nonsymmetrical laser-pulse propagation in capillary tubes with inner radius smoothly varying with the capillary length is proposed. Using this model, the use of capillaries with specially profiled entrance sections (particularly cone matching elements) for improving the coupling of the laser energy into a capillary and avoiding capillary ablation is analyzed. It is shown that cone entrances with a sufficiently small angle (αcone≠10 mrad) help decrease the longitudinal energy flux and ablation of the entrance face of a capillary, but do not remove the requirements on the precision of laser-pulse focusing necessary to obtain regular laser fields, characterized by a symmetrical intensity distribution, centered on the capillary axis. To achieve regular laser fields without strong transverse gradients, the angle between the laser and capillary axes has to be smaller than 1 mrad for capillaries with an inner radius of the order of tens of microns. © 2012 American Physical Society.


Danilov I.M.,Moscow Institute of Physics and Technology | Iorish V.S.,RAS Institute for High Energy Densities | Son E.E.,Moscow Institute of Physics and Technology
High Temperature | Year: 2011

A numerical simulation is carried out of the exothermal heterogeneous reaction of cumene oxidation on the basis of a homogeneous model of bubble liquid. The thermal properties of the bubble medium are determined according to the proposed model. The influence of different factors is investigated on an oxidation level with a volume gas content value of more than 0.5. © Pleiades Publishing, Ltd., 2011.

Loading RAS Institute for High Energy Densities collaborators
Loading RAS Institute for High Energy Densities collaborators