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Vol 59, No 3 (2016)

Nuclear Experimental Technique

Multiturn fast extraction of the proton beam from the U-70 synchrotron

Rudko V.D., Avramenko S.V., Loguinov A.A., Maximov A.V., Ovsienko M.P., Raev V.D., Fedotov Y.S.

Abstract

A novel system for high-energy beam extraction from the U-70 proton synchrotron to the external beam transfer line (i.e., a multiturn fast extraction system) is described. The beam is forced into the first upstream ejection device—an electrostatic deflector—by means of fast dipole bump magnets with the field rise time of 50–100 μs (equivalent of 10–20 beam turns). The fast bump magnets and their power supplies are described. The first experimental results acquired during trial operation of the multiturn fast extraction system in 2014 are presented. From these results, it is apparent that the extracted beam parameters are close to those obtained with the available single-turn fast extraction system.

Instruments and Experimental Techniques. 2016;59(3):325-330
pages 325-330 views

An automated absolute proton monitor based on a two-section ionization chamber

Amerkanov D.A., Gorkin G.I., Ivanov E.M., Ivanov N.A., Lobanov O.V., Pashuk V.V.

Abstract

An absolute proton beam monitor based on a two-section ionization chamber is described. Flux value data are read out of the monitor in the real-time mode without its preliminary calibration. A softwarecontrolled circuit for experimental data acquisition and processing has been developed.

Instruments and Experimental Techniques. 2016;59(3):331-332
pages 331-332 views

A method for measuring the detector response function for monochromatic electrons based on Compton scattering

Bakhlanov S.V., Derbin A.V., Drachnev I.S., Kayunov A.S., Muratova V.N., Semenov D.A., Unzhakov E.V.

Abstract

A method for calibrating the energy scale of a scintillation detector using γ rays has been proposed and implemented. The technique is based on Compton scattering in the scintillation detector, followed by photoelectric absorption of a scattered γ-ray photon in a Ge detector. The novelty of the method consists in placing the γ-ray source and the scintillation and Ge detectors tightly to each other. The method is efficient for detectors with a low-Z material for which the ratio of the cross sections for Compton scattering and photoeffect is great in value and the attenuation length of the γ-ray flux is comparable to the detector dimensions. The described technique can be used to precisely investigate the dependence of the light yield in a scintillator on the electron energy.

Instruments and Experimental Techniques. 2016;59(3):333-336
pages 333-336 views

Application of Computers in an Experiment

A hardware–software complex for controlling the pulsed power source of the T-15U tokamak

Pavlov V.M., Baystrukov K.I., Merkulov S.V., Golobokov Y.N., Kachkin A.G., Mezentsev A.A., Kim V.L., Lee A.M., Ilinych S.A., Sokolov M.M., Nikolaev A.V.

Abstract

Results of designing of the hardware complex intended to control pulsed power systems of the T-15U tokamak are considered. The complex is based on digital and microprocessor components and ensures control over the power circuit of high-power semiconductor converters, monitoring of load parameters, and emergency protection of the electrical equipment. The complex is optimized for application in distributed multichannel power systems in which it is important that a group of converters operate synchronously into a complicatedly configured load.

Instruments and Experimental Techniques. 2016;59(3):337-343
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Pulse-signal digitizer for high-temperature plasma diagnostic systems

Ivanenko S.V., Kvashnin A.N., Kotelnikov A.I., Moiseev D.V., Puryga E.A., Khilchenko A.D., Khilchenko V.A., Shvyrev V.G., Ivanova A.A., Zubarev P.V.

Abstract

A pulse-signal digitizer for laser, neutron, and gamma diagnostics of high-temperature plasma at the GOL-3 and GDL (Budker Institute of Nuclear Physics Siberian Branch, Russian Academy of Sciences) is described. The architecture of a two-channel 12-bit ADC12500PXIe digitizer with a sampling rate of 500MHz, a PXI Express interface, and a built-in reconfigurable digital signal processing unit is described. The results of ADC12500PXIe metrological tests are presented: its signal-to-noise ratio (SNR), jitter, effective number of bits, and differential and integral nonlinearities are shown. The high-temperature plasma diagnostic systems based on ADC12500PXIe are considered. The structure of the digital signal processing unit that was modified for a prototype of the ITER vertical neutron camera (Cadarache, France) is described.

Instruments and Experimental Techniques. 2016;59(3):344-350
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Electronics and Radio Engineering

Investigation of high-voltage integral pulse thyristors in single-pulse and pulse-train modes

Grekhov I.V., Zhmodikov A.L., Korotkov S.V., Prizhimnov S.G., Fomenko Y.L.

Abstract

The results of studying the switching capabilities of recently developed high-voltage integral pulse thyristors (HIPTs) with a working area of 0.45 cm2 and an operating voltage of 3 kV are presented. A silicon chip of a thyristor consists of a large number of microthyristor cells that are enabled strictly synchronously with a control-current pulse, thus providing low switching energy losses and allowing a current of up to 8 kA at a pulse duration of 1.5 μs to be switched within 500 ns in a single-pulse mode. The HIPT switching-off time is several microseconds when, after a power-current pulse terminates, a field-effect transistor with a low (tens of milliohms) channel resistance closes the emitter–base circuit. The low switching energy loss and the short switching-off time made it possible to use HIPTs in the mode of switching current pulses with an amplitude of 500 А at a frequency of 50 kHz.

Instruments and Experimental Techniques. 2016;59(3):351-355
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A modular drift step-recovery diode generator for nanosecond pulse technologies

Korotkov S.V., Aristov Y.V., Zhmodikov A.L., Kozlov A.K., Korotkov D.A., Kuznetsov A.S., Meshalkina M.N.

Abstract

A generator of nanosecond pulses with an energy of ~50 mJ, which provides switching of voltage pulses with an amplitude of ~17 kV and a rise time of ~4 ns at a repetition frequency of 8 kHz to a 75-Ω resistive load, is described. The load is matched to the generator output cable. The generator is based on an opening switch in the form of a unit of drift step-recovery diodes (DSRDs). The conditions for the efficient operation of DSRDs are provided by six self-contained modules each of which contains an IGBT transistor and a step-up saturable-core transformer. The results of an experimental study of the generator are presented. They indicate a high efficiency of the developed modular circuit, which makes it possible to increase the switched energy virtually in proportion to the number of used modules, and the possibility of reducing the switching energy loss in the DSRD unit in proportion to the number of diode assemblies connected in parallel. It is shown that the generator can be used for producing ozone and high-purity silicon tetrafluoride and also in an apparatus for purifying air of organic pollutants.

Instruments and Experimental Techniques. 2016;59(3):356-361
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A high-voltage high-current switch on the basis of triggered vacuum switches

Akhmetgareev M.R., Ivanov V.P., Menakhin L.P., Sidorov V.A.

Abstract

A KV-25-300 high-voltage switch for dc voltages of up to 25 kV and currents of up to 300 kА for pulse powering of loads at a pulse rise rate of up to 10 kA/μs was developed and tested. The switch consists of two series-connected RVU-43-1 triggered vacuum switches, thus making it possible to reduce the breakdown probability at the maximum operating voltage to a value of <10–7. The total switching-on time delay relative to the optical control pulse is 4 ± 0.5 μs. The results of measurements and calculation of the electric strength of RVU-43-1 and KV-25-300 and the results of switching tests of the latter are presented.

Instruments and Experimental Techniques. 2016;59(3):362-367
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High power microwaves generation from intense relativistic electron beam using Kali-1000 pulse power system

Satyanarayana N., Rajawat R.K., Basu S., Durga Prasad Rao A., Mittal K.C.

Abstract

Intense relativistic electron beam (IREB) is generated using Kali-1000 (Kilo Ampere Linear Injector) pulse power system, providing input electric power of 4 GW and stored energy of 1000 J. IREB is used for generating Non Ionizing (High Power Microwaves, HPM) and Ionizing (Flash X-rays) radiation. The present manuscript discusses generation of HPM by Kali-1000 system using an axial Virtual cathode oscillator. Kali-1000 pulse power system is a low impedance (~4 Ω) high voltage generator, consisting of Radial Tesla transformer to step up the voltage from 28 to 300 kV in 5 μs, which energizes the line, pulse discharged by a self triggered pressurized SF6 closing switch across a Relativistic Electron Beam (REB) diode load. The typical electron beam parameters are 300 kV, 15 kA and 100 ns with a current density of 3–4 hundreds of amperes per square centimeter. Experiments are carried with a REB diode consisting of graphite cathode and SS anode mesh. Measured pulse duration of HPM pulse (FWHM) varies from 70 to 110 ns on shot-to-shot basis. The major operating output frequencies have been measured to be 5.8 and 6.2 GHz within a range of 4.8–6.7 GHz using B-dot magnetic field sensor coupled to high frequency digital oscilloscope. Microwave output power from the virtual cathode oscillator has been measured to be 50 MW using double ridged waveguide horn antenna coupled with Schottky detector diode. The estimated beam to microwave power conversion efficiency is thereby found to be 1.1%. Particle-in-Cell (PIC) simulation has been performed for a set of Vircator experiments being driven by the Kali-1000 system. Experimentally measured cathode current, dominant output frequency, radiation pattern, etc., have been compared with simulation results and are in good agreement. The dominant emission mode from the virtual cathode oscillator is shown to be the TE01 mode based on the emission pattern of microwave induced air breakdown in this experiment.

Instruments and Experimental Techniques. 2016;59(3):368-373
pages 368-373 views

A dual-wave atmosphere transparency radiometer of the millimeter wave range

Nosov V.I., Bolshakov O.S., Bubnov G.M., Vdovin V.F., Zinchenko I.I., Marukhno A.S., Nikiforov P.L., Fedoseev L.I., Shvetsov A.A.

Abstract

The MIAP-2 radiometric complex intended for measuring the atmospheric absorption in the millimeter wavelength range (2 and 3 mm) is described. The complex is based on two solid-state modulation radiometers with wave ranges of 84–99 GHz and 132–148 GHz, which are equipped with horn-lens antennas. The device determines an optical depth in the millimeter wave range using the atmospheric-dip method and the absolute signal calibration method in the fully automated mode under the remote control via the Internet. A set of observations was performed in the stationary mode and in mountain expedition conditions. The reliability of the device was evaluated from 2-year operation results.

Instruments and Experimental Techniques. 2016;59(3):374-380
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A power supply for a copper bromide vapor laser

Troitsky V.O., Dimaki V.A., Filonov A.G.

Abstract

A power supply for a copper bromide vapor laser with stepwise charging of the operating capacitance is presented. A technical solution intended for charging the operating capacitance to energies of about 1 J under automatic control of laser operation is described. The effect of the electric circuit parameters on the charging process of the operating capacitance is shown. The operating characteristics of the device are presented.

Instruments and Experimental Techniques. 2016;59(3):381-384
pages 381-384 views

General Experimental Techniques

Startup of the Proton Radiographic Facility at the U-70 accelerator

Andrianov A.I., Afonin A.G., Gusev I.A., Zyatkov O.V., Ignashin N.A., Larionov A.V., Ludmirsky E.A., Maximov A.V., Matyushin A.A., Minchenko A.V., Mikheev M.S., Peleshko V.N., Rudko V.D., Terekhov V.I., Tyurin N.E., Fedotov Y.S.

Abstract

The first results of Proton Radiographic Facility operation on the beam with energies of 50–70 GeV extracted from the U-70 synchrotron at the Institute for High Energy Physics are presented. This facility is capable of forming proton radiographic images of samples with an optical thickness as large as 450 g/cm2 and a field of view of 220 mm or more.

Instruments and Experimental Techniques. 2016;59(3):385-392
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Angular dose variations from 320 kV rod pinch diode flash X-ray experiments on the modified Kali-1000 Pulsed Power System

Satyanarayana N., Waghmare N., Chavhan S., Rajawat R.K., Durga Prasada Rao A., Mittal K.C.

Abstract

This paper highlights the angular distribution of radiation dose emitted from a rod-pinch diode. The typical RP diode employed used a small diameter (1–2 mm) anode rod extended through a cathode aperture (5–8 mm). The diode chamber is maintained at 2 × 10–5 Torr vacuum by a rotary backed diffusion pump. Experiments performed on a modified Kali-1000 Pulsed Power System (300 kV, 30 kA, 100 ns) were aimed at optimizing the source by maximizing the figure of merit (dose at 1 m in rad/spot diameter2 in mm2) with minimizing of the diode impedance. The typical electron beam parameters used in the experiments are 240–320 kV, 6.5–27.5 kA, 100 ns, with a few hundreds of kA/cm2 current density. The radiation emitted from a rod-pinch diode is measured using thermoluminescence dosimeters at an angular interval of 15° on either side of the rod in horizontal and vertical plane with different aspects ratio ranging from 2.5 to 10.0. Experimentally found that the radiation dose produced from the rod pinch diode configuration is maximum in the axial direction and decreases with angular variation on either side of the axis in horizontal and vertical planes, which indicates the directivity of the source. Maximum radiation dose at 1 m distance on the axial line is ranging from 42 to 307 mR.

Instruments and Experimental Techniques. 2016;59(3):393-397
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A pulsed generator of X-ray bremsstrahlung with a high peak exposure rate

Bakshaev Y.L., Dolgachev G.I., Kazakov E.D., Kalinin Y.G., Maslennikov D.D., Mizhiritskii V.I., Fedotkin A.S., Khodeev I.A., Shvedov A.A.

Abstract

A new pulsed generator of X-ray bremsstrahlung based on an inductive energy storage and a plasma opening switch is described. The radiation parameters are as follows: the peak exposure rate is as high as 5 × 109 R/s, and the dose is as high as 800 R.

Instruments and Experimental Techniques. 2016;59(3):398-403
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A gas-discharge He–Ne laser generating monochromatic radiation with λ = 1.52 μm for testing telecommunication systems

Atutov S.N., Sorokin V.A.

Abstract

The results of a detailed study of a gas-discharge He–Ne laser that generates monochromatic radiation with λ = 1.52 μm are presented. Such important laser parameters as the divergence of laser radiation, the laser power as a function of the temperature, the laser-power stability, and noise and spectral characteristics of radiation were measured. The attained parameters of laser radiation in the aggregate occurred to be virtually ideal for using the laser in tests of telecommunication systems. The possibility of laser microminiaturization is shown, which is of interest when using it under the conditions of a high level of electromagnetic noise.

Instruments and Experimental Techniques. 2016;59(3):404-411
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Characteristics of a pulse–periodic CO2 laser for applications in the field of laser-produced plasma

Satov Y.A., Shumshurov A.V., Vasilyev A.A., Balabaev A.N., Losev A.A., Khrisanov I.A., Rerikh V.K.

Abstract

The design of a pulse–periodic СО2 laser oscillator that operates at a high level of the specific energy deposition into a self-sustained discharge is described. The laser is intended for generating pulses with a high-density radiation flux in a laser-plasma generator of multiply charged ions at the Institute of Theoretical and Experimental Physics (ITEP). The results of investigations of the spatiotemporal and energy characteristics of laser output radiation in a wide range of the discharge excitation level and the mixture composition are presented. The optimal conditions are determined under which the oscillator provides an output energy of >10 J in a pulse with a duration of ~28 ns and a record specific peak radiation power of 190 MW per liter of the active volume of a CO2: N2: He mixture. The high quality of the spatial characteristics was confirmed in measurements of the radial energy-density distribution in the far-field zone, whose characteristic size is close to the diffraction limit.

Instruments and Experimental Techniques. 2016;59(3):412-419
pages 412-419 views

A device for free-carrier recombination lifetime measurements

Kobeleva S.P., Anfimov I.M., Schemerov I.V.

Abstract

The design of a microwave system, the user interface, and the basic characteristics of noncontact equipment for measuring the recombination lifetime of free charge carriers in semiconductor materials by the photoconductivity-decay method are described. The features of the microwave-system design eliminate the need for a microwave circulator and other expensive elements of the systems without a loss in the equipment sensitivity. This substantially simplifies the design and provides automated measurements of the free-carrier lifetime in silicon single crystals in a range of 0.2 μs to tens of milliseconds. The upper measurement limit is determined by the geometrical dimensions of a sample and the surface treatment quality. The results of measuring the photoconductivity relaxation time in reference single-crystal silicon samples are presented.

Instruments and Experimental Techniques. 2016;59(3):420-424
pages 420-424 views

A magnetometer of weak quasi-stationary and high-frequency fields on resonator microstrip transducers with thin magnetic fields

Babitskii A.N., Belyaev B.A., Boev N.M., Skomorokhov G.V., Izotov A.V., Galeev R.G.

Abstract

A high-sensitivity magnetometer for simultaneous measurements of three components of a weak quasi-stationary or high-frequency magnetic-field vector was developed and investigated. Microstrip structures that are based on irregular resonators serve as the magnetometer transducers. An anisotropic thin-film magnetic structure is used as the sensing element. This structure consists of two thin magnetic films that are prepared by magnetron sputtering of a Ni75Fe25 permalloy target and separated by a silicon monoxide layer. It is demonstrated that the transducer exhibits the maximum sensitivity, when the easy magnetization axis of the film structure is orthogonal to the polarization direction of the pumping microwave magnetic field in the microstrip resonator and at an optimal value of a constant magnetic bias field and its optimal deflection from the pumping-field polarization direction which is parallel to it. The magnetometer is characterized by a wide dynamic range of measured magnetic fields, 10–10–10–4 Т, and a wide frequency range, 10–1–105 Hz.

Instruments and Experimental Techniques. 2016;59(3):425-432
pages 425-432 views

Physical Instruments for Ecology, Medicine, and Biology

Ground-based microwave spectroradiometer for thermal sounding of the troposphere

Shvetsov A.A., Ryskin V.G., Kulikov M.Y., Kukin L.M., Fedoseev L.I., Shchitov A.M., Feigin A.M.

Abstract

The laboratory model of a mobile solid-state uncooled microwave spectroradiometer, operating in the frequency range of 50 to 55 GHz is described. It is designed for remote passive monitoring of the tropospheric temperature. The spectroradiometer consists of a heterodyne receiver with a low noise amplifier at input and 8-channel spectrum analyzer. To ensure the internal calibration of the intensity of the received atmospheric radio emission using the built-in unit type modulator-calibrator based on GaAs diodes with the Schottky barrier. The antenna system of the spectroradiometer consists of a teflon enlightened lens and conical corrugated horn. The device is equipped with an automated control system process measurement, calibration, and data pre-processing.

Instruments and Experimental Techniques. 2016;59(3):433-436
pages 433-436 views

Features of application of the extremely-low-frequency–very-low-frequency atmospherics spectrum analyzer for monitoring the earth–ionosphere waveguide state

Galakhov A.A., Kirillov V.I., Akhmetov O.I.

Abstract

Features of the operation algorithm of the atmospherics spectrum analyzer and its application for diagnosing the earth–ionosphere waveguide are discussed. It is shown that the selected structure of the spectrum analyzer is expedient. The results are based on the seasonal data obtained at two Polar Geophysical Institute (PGI) observatories, which are located at polar latitudes (“Lovozero” in the Murmansk oblast and “Barentzburg” at the Spitsbergen archipelago).

Instruments and Experimental Techniques. 2016;59(3):437-441
pages 437-441 views

Physical simulation of the action of atomic oxygen and vacuum ultraviolet radiation on polymer materials in the earth’s ionosphere

Shuvalov V.A., Tokmak N.A., Reznichenko N.P.

Abstract

A procedure of the physical (bench) simulation of the long-term interaction of polymer materials with flows of atomic oxygen and vacuum ultraviolet radiation in the earth’s ionosphere is designed. The efficiency of the bench measurements of mass losses of kapton-H and PM-1E polyimides, polyethylene, and FEP Teflon is confirmed by results of satellite measurements. The dependences of degradation of polymer films on the fluence of atomic oxygen are determined. They allow one to forecast time changes of mass and geometric characteristics of polymers during the whole operating period in the ionosphere. The synergetic effect of the action of the near-satellite environment on the ablation of the polymer films characterizes threshold ratio values of the vacuum ultraviolet energy flow to the atomic oxygen flow.

Instruments and Experimental Techniques. 2016;59(3):442-450
pages 442-450 views

Experimental research of dynamic loads formed upon breaking of a gravitational wave on a sloping bottom

Kushnir V.M., Sholar S.A., Dushko V.R.

Abstract

The description of instruments and equipment that are used for performing experimental research of dynamic loads, which are formed upon breaking of a gravitational wave on a sloping bottom, is presented. Measurements are performed in the wave basin of the Sevastopol State University, the slope of whose bottom can be varied. The measurement system includes two highly sensitive digital wave recorders, two diaphragm pickups of dynamic loads, a digital filter, a switchboard, and a personal computer. To independently determine the wave height and study the wave-breaking processes in the region of the sloping bottom, filming of wave profiles against the background of a coordinate grid with a mesh size of 50 mm and the wave-destruction processes is additionally performed. The measurement results are compared to the described results of known model processes of the formation of dynamic loads.

Instruments and Experimental Techniques. 2016;59(3):451-457
pages 451-457 views

A membrane separator interface for mass-spectrometric analysis of desflurane, propofol, and fentanyl in blood plasma and cerebrospinal fluid

Elizarov A.Y.

Abstract

An easy-to-operate mass-spectrometric membrane separator interface, which is intended for measuring the concentrations of anesthetic preparations in biological fluids (blood plasma and cerebrospinal fluid), is described. Biological fluids are sampled during balanced inhalation (desflurane, fentanyl) anesthesia and total intravenous (desflurane, propofol) anesthesia. In the design of the mass-spectrometer interface, a hydrophobic membrane that separates anesthetic preparations from biological fluids is used: inhalation anesthetic desflurane, hypnotic propofol, and analgetic fentanyl. It was revealed that the membrane does not degrade during multiple (up to 30 cycles) measurements. The possibility of using the interface for measuring the absolute concentrations of desflurane and propofol in blood plasma and cerebrospinal fluid when studying the properties and degree of degradation of the blood–brain barrier in the in situ mode.

Instruments and Experimental Techniques. 2016;59(3):458-461
pages 458-461 views

A barrierless pulse discharge cell

Andreev V.V., Pichugin Y.P.

Abstract

A barrierless plasmachemical ozone generator, operating on the corona discharge, is studied. A high-voltage pulse power source and a discharge chamber are its basic elements. For obtaining high-voltage pulses with duration of several tens nanoseconds, a rotating discharger is connected to the output of a highvoltage direct-current source. The studied barrierless discharge chamber is characterized by a high efficiency of ozone synthesis, design simplicity, and minimal sizes. As compared to discharge chambers of other types, its advantage is that a corona discharge virtually fully fills its volume. Due to this fact, ozone is synthesized almost in the whole volume of the discharge chamber, resulting in attaining its high concentration at the chamber output. A productivity equal to 30 g/m3 and higher was reached in the experiments.

Instruments and Experimental Techniques. 2016;59(3):462-465
pages 462-465 views

Laboratory Techniques

A silicon sublimation source for molecular-beam epitaxy

Shengurov V.G., Denisov S.A., Chalkov V.Y., Shengurov D.V.

Abstract

A sublimation source for molecular-beam epitaxy of silicon layers with a rectangular wafer of doped Si is described. The wafer is attached to springing molybdenum clamps with a smaller width of the contact pad than the wafer width, thus providing the possibility of the evaporation of Si atoms with a high flux density. The criteria for choosing the geometry of the contact pads, on which the silicon wafer–source is fixed, are presented.

Instruments and Experimental Techniques. 2016;59(3):466-469
pages 466-469 views

Nano-vibration measurements using the photoelectromotive force effect in the GaAs crystal

Gao X., Zhang B., Feng Q., Xie X., Yang L.

Abstract

A broadband, nano-vibration measuring method based on the photoelectromotive force (photo-EMF) effect of semiconductor crystal is presented. A He-Ne-laser homodyne interferometer system is used as a light source and a GaAs crystal is used as a photodetector. The signal beam, which is modulated by the vibration, interferes with the reference beam, and a vibrating interference pattern is created on the surface of the GaAs crystal. Due to the photo-EMF effect, an alternating current signal, which relates to the vibration, is produced. We found the optimum parameters for the measurements by adjustments of the intensity ratio of the two beams, the angle between the beams and the interelectrode spacing on the GaAs crystal. The system can detect the vibration amplitude about several nanometers. The results of measurements of the vibrations of the PZT sample are well coincided with those obtained by TEMPO200 (Bossa Nova Technologies, America) system.

Instruments and Experimental Techniques. 2016;59(3):470-475
pages 470-475 views

An instrument for measuring acoustic wave velocities in metals and alloys

Murav’ev V.V., Zlobin D.V., Len’kov S.V., Zverev N.N.

Abstract

A circuit and principle of operation of the instrument for measuring ultrasonic-wave propagation times, which is based on the autocirculation method using up-to-date electronics, are described. The circuit solutions, allowing one to sufficiently decrease the measurement error, are presented. The methods that ensure a high determination accuracy of ultrasonic-wave velocities in steel samples are considered. Areas of instrument applications are shown.

Instruments and Experimental Techniques. 2016;59(3):476-480
pages 476-480 views

Compensation for the temperature effect on operation of laser interferometers

Dolgikh S.G., Budrin S.S., Plotnikov A.A.

Abstract

A temperature-compensated design of laser meters of hydrosphere pressure variations and laser hydrophones has been developed and introduced. Owing to this design, it is possible to perform long-term measurements without tuning the optical section of an instrument.

Instruments and Experimental Techniques. 2016;59(3):481-482
pages 481-482 views

Thermostatting of the RED-100 liquid-xenon emission detector

Bolozdynya A.I., Efremenko Y.V., Sidorenko A.V., Sosnovtsev V.V., Tolstukhin I.A., Shakirov A.V., Shafigullin R.R., Khromov A.V.

Abstract

The thermal stabilization system of the RED-100 liquid-xenon two-phase emission detector for the experiment aimed at detecting the effect of coherent neutrino scattering off xenon nuclei has been tested. The system is based on thermosyphons (closed two-phase heat pipes) that are filled with nitrogen and use liquid nitrogen boiling at atmospheric pressure as a cooler. The system is capable of keeping the working medium of the RED-100 detector at a temperature of 167 K with a precision of <1 K.

Instruments and Experimental Techniques. 2016;59(3):483-486
pages 483-486 views