2009

Andramanov A. V., Kabaev S. A., Lazhintsev B. V., Nor - Arevyan V. A., Pisetskaya A. V., Selemir V. D.  High - pulse - repetition - rate UV  lasers with the inductance - capacitance discharge stabilisation  //  Quantum Electronics, 2009, Volume 39, Issue 2, Pages 147 - 153

RFNC - VNIIEF, Sarov, Russian Federation

Compact high - pulse - repetition - rate  XeF and  KrF excimer lasers and an N₂  laser with plate electrodes and the inductive - capacitance discharge stabilisation are studied. The composition and pressure of the active medium of lasers are optimised for obtaining the maximum output energy and maximum pulse repetition rate at comparatively low ( no more than 19 m s^-1 ) active - medium flow rates in the interelectrode gap. The pulse repetition rate achieved 4 - 5 kHz  for the relative root - mean - square deviation of the laser pulse energy less than 2%. It is found that the energy of the N₂ - laser pulses changes periodically under the action of acoustic perturbations appearing at high pulse repetition rates. It is shown that the use of the inductance - capacitance stabilisation of the discharge provides the increase in the maximum pulse repetition rate by  0,5 - 1,5 kHz ( depending on the active medium type ). It is found that the stability of the output energy and maximum pulse repetition rate depend on the location of preionisation sparks with respect to the gas flow direction. Some ways for the development of the technology of plate electrodes and inductance - capacitance discharge stabilisation are proposed.

Andramanov A. V., Voevodin D. D., Vysotskii A. V., Kabaev S. A., Lazhintsev B. V., Nor - Arevyan V. A., Pisetskaya A. V., Selemir V. D.   High - repetition - rate plate - electrode CO₂  laser  //  Quantum Electronics, 2009, Volume 39, Issue 12, Pages 1102 - 1106

RFNC - VNIIEF, Sarov, Russian Federation

A high - repetition - rate CO₂  laser with the inductive - capacitive discharge stabilisation is studied for the first time. A multisection discharge gap of length 250 mm  was formed by pairs of anode - cathode plates arranged in the form of a broken line. The width of the discharge region between each pair of the plates was ~ 1,3 mm and height ~ 12 mm. The cross section of the laser beam on the output mirror of the resonator was ~ 6 × 8 mm. The maximum output energy of the laser using the CO₂ : N₂ : He = 32 : 32 : 96  Torr mixture was 15,9 mJ, the lasing efficiency being 1,7%.  For a relatively low gas flow rate of 19 m s^-1, a CO₂  laser pulse repetition rate of 3 kHz was achieved, the relative root - mean - square deviation of the pulse energy being within 5%. The average output power of the laser was ~ 40 W.

Bobashev S. V.,^a Mende N. P.,^a Popov P. A.,^a Sakharov V. A.,^a Berdnikov V. A.,^b Viktorov V. A.,^b Oseeva S. I.,^b Sadchikov G. D.^b   Algorithm for determining the aerodynamic characteristics of a freely flying object from discrete data of ballistic experiment.  Part 1  //  Technical Physics, 2009, Volume 54, Issue 4, Pages 504 - 510

^a  Ioffe Physico - Technical Institute, Russian Academy of Sciences, ul. Politekhnicheskaya 26, St. Petersburg 194021, Russian Federation
^b  RFNC - VNIIEF, Sarov, Russian Federation

An algorithm for solving the inverse problem of dynamics is described. It is intended for processing trajectory data for a freely flying object that are acquired in ground - based ( laboratory ) simulation on a ballistic range with the aim of determining the aerodynamic characteristics of the object.

Bobashev S. V.,^a Mende N. P.,^a Popov P. A.,^a Sakharov V. A.,^a Berdnikov V. A.,^b Viktorov V. A.,^b Oseeva S. I.,^b Sadchikov G. D.^b  Algorithm for determining the aerodynamic characteristics of a freely flying object from discrete data of ballistic experiment.  Part 2  //  Technical Physics, 2009, Volume 54, Issue 4, Pages 511 - 519

^a  Ioffe Physico - Technical Institute, Russian Academy of Sciences, ul. Politekhnicheskaya 26, St. Petersburg 194021, Russian Federation
^b  RFNC - VNIIEF, Sarov, Russian Federation

In part 1 of this paper, an algorithm for numerically solving the inverse problem of motion of a solid through the atmosphere is described that constitutes the basis for identifying the aerodynamic characteristics of an object from trajectory data and the respective identification procedure is presented. In part 2, methods evaluating the significance of desired parameters and adequacy of a mathematical model of motion, approaches to metrological certification of experimental equipment, and results of testing the algorithm are discussed.

Chelpanov V. I., Golyakov P. I., Kornilov V. G., Volkov A. A., Dubinov A. E., Selemir V. D., Zhdanov V. S.  Collective acceleration of xenon ions in a plasma - anode vircator  //  Technical Physics, 2009, Volume 54, Issue 1, Pages 142 - 145

RFNC - VNIIEF, Sarov, Russian Federation

The collective acceleration of xenon ions in a plasma-anode vircator is studied. It is shown that the energy of accelerated ions may reach 900 MeV. The image of a bremsstrahlung source on the target suggests effective transport of relativistic electrons in the drift channel.

Koblova O. N., Kudasov Y. B.  Prestressed high - magnetic - field solenoids  //  Technical Physics Letters, 2009, Volume 35, Issue 9, Pages 850 - 852

RFNC - VNIIEF, Sarov, Russian Federation

The effect of mechanical preloading at a stress level that is close to the yield point of a material on the strength of a high - magnetic - field  ( HMF ) solenoid is theoretically studied. A comparative analysis of the properties of prestressed HMF coils of various designs is carried out. A new concept of stressed composite solenoid is developed.

Karelin V. I., Tren'Kin A. A.   High - energy electrons in nanosecond high - voltage discharges developing in the regime of microstructured current channels  //  Technical Physics Letters, 2009, Volume 35, Issue 5, Pages 407 - 409

RFNC - VNIIEF, Sarov, Russian Federation

A mechanism responsible for the generation of high - and anomalous - energy electrons is formulated on the basis of a fractal model of the spatial structure of nanosecond gas discharges. The proposed mechanism admits the acceleration of electrons both in the stage of interelectrode gap bridging and in the stage of conduction.

Lin E.  Determining the growth rate of nanostructured particles of light actinides at high and moderate temperatures  //  Technical Physics Letters, 2009, Volume 35, Issue 5, Pages 418 - 420

RFNC - VNIIEF, Sarov, Russian Federation

Analytical expressions for evaluating the dimensional and temporal characteristics of polymorphous transformations in light actinides under the action of intense external factors are obtained based on phenomenological notions of the behavior of nanostructured objects with quasi - covalent bonds.

Dubinov A. E.  Exact stationary solution of the Kompaneets kinetic equation  //  Technical Physics Letters, 2009, Volume 35, Issue 3, Pages 260 - 262

RFNC - VNIIEF, Sarov, Russian Federation

Exact stationary solutions of the Kompaneets kinetic equation, which describes the spectra of photons interacting with a rarefied electron gas are obtained and analyzed for the first time. Solutions describing the stationary spectra of comptonization in a photon flux along the frequency axis are expressed through the Heun functions. It is shown that the photon input and output points always correspond to finite frequencies.