Features of the tomography of the marine crust are described, based on the use of coastal laser strainmeters and broadband low-frequency underwater acoustic projectors. This approach is useful in ...studying the structure and composition of the marine crust in shelf areas, including ones covered with ice without destroying it. Numerous experimental studies have established that at sea depths equal to or less than half the length of a hydroacoustic wave generated by low-frequency underwater acoustic projectors, the hydroacoustic energy is mainly transformed into Rayleigh-type surface waves that radiate through the bottom on the hydroacoustic source–coast path.
Drift chamber for the CMD-3 detector Grancagnolo, F.; Fiore, G.; Ignatov, F.V. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2010, Letnik:
623, Številka:
1
Journal Article
Recenzirano
The construction, digitizing electronics and results of test with cosmic rays of cylindrical drift chamber for CMD-3 detector are described. To uniformly fill the sensitive volume small hexagonal ...cells were chosen. The coordinate along the wire is measured by charge division technique. A resolution in the R–ϕ-plane of better than 110μm and about 3mm along the wire as well as a dE/dx resolution of about 12% were obtained in cosmic test runs.
A time-of-flight detector based on microchannel plates (MCP) is under development. The main goal of this work is the creation of a radiation hard large area detector providing 10 ps time resolution ...in strong magnetic field. The conceptual detector design is described in details.
A radiating hydroacoustic system intended to generate harmonic and phase-shifted hydroacoustic signals in the frequency band of 1 Hz with a center frequency in the range of 19−26 Hz is described. The ...maximum change in the radiator volume may be as large as 0.0123 m
3
, which corresponds to a radiated acoustic power of 1000 W at a frequency of 20 Hz in the boundless water space. The prospects of using the system for carrying out research are demonstrated via the results of its testing on the shelf of the Sea of Japan.
Development of a picosecond MCP based particle detector Barnyakov, A.Yu; Barnyakov, M.Yu; Blinov, V.E. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2020, Letnik:
952
Journal Article
Recenzirano
A time-of-flight detector based on microchannel plates (MCP) is under development. The main goal is the creation of a radiation hard large area detector providing ∼10 ps time resolution for single ...charged particle in strong magnetic field. Conceptually, the detector consists of Cherenkov radiator covered with semitransparent photocathode followed by a chevron pair of MCPs. The detector design and the status of the development are reported.
On the basis of experimental data obtained during a comprehensive experiment in Vityaz Bay of the Sea of Japan using onshore laser strainmeters and a low-frequency hydroacoustic emitter generating ...complex phase-manipulated signals with a central frequency of 33 Hz, we developed the basic principles of contactless tomography of the Earth’s crust in the shelf regions of various seas, including those covered by ice, making it possible to determine efficiently the structure and composition of the upper Earth’s crust under seas.
A method for experimental studies of crustal structure and composition in marine areas during warm and cold seasons is described. The method employs an electromagnetic low-frequency hydroacoustic ...transmitter, which generates complex phase-shift keyed signals (M-sequences) in water with a center frequency of 33 Hz, and a mobile laser strainmeter with a measuring arm length of 6 m. In an area with a sea depth of 14 m, the transmitter was lowered to a depth of 12 m. Processing of the obtained experimental data revealed five arrivals of transmitted phase-shift keyed signals to the laser strainmeter, which propagated along the layer boundaries of the upper crust of marine areas. The propagation velocities of these signals have been determined. In winter, they are approximately 2600, 2140, 1750, 1550, and 1280 m/s; in spring, 2250, 1950, 1700, 1480, and 1300 m/s. The calculated velocities agree well with the model data. Future results will make it possible to create a technology to remotely study crustal structure and composition in shelf zones, including shelf zones covered by ice, without destroying it.
The characteristics of a compact Nd : YAG/Cr : YAG laser with segmented end pumping using a bundle of seven optical fibres are presented. In the regime of optical coupling of thus formed seven laser ...channels, pulses with an energy up to , as well as their trains, are obtained. The used method makes it possible to scale the energy and power of lasers of this type with controlled spatial beam profile.
This study dealing with application of shore based laser strainmeters for recording the complex phase shift signals (M sequences) has shown the feasibility of this method for solving the tomographic ...and inversion problems related to investigation of the structure and composition of the Earth's crust in marine shelf zones.
The strategy for the development of nuclear power presupposes the construction of thermal water-cooled reactors and fast reactors 13. At present, water moderated and cooled power reactors are the ...foundation of our countrys nuclear power. The organizations of the State Corporation Rosatom have developed designs for new-generation reactor setups AES-2006 and VVER-TOI, which are the result of evolutionary development and improvement of operating water moderated and cooled power reactors, which proved their reliability in thousands of reactor-years of accident-free operation. To secure the possibility of increasing the power and validating the serviceability of new passive safety systems for VVER, a large-scale program of thermophysical and experimental studies has been completed.