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Cosmic ray muonography is a novel technique for imaging of the internal structures of large natural and industrial objects. It exploits the capability of high energy muons from cosmic rays to penetrate large thicknesses of large subjects to be studied, in order to obtain a density map. It uses muon flux attenuation and absorption in materials of investigated objects. Nuclear emulsions are tracking detectors well suited to be employed in muonography for investigations of inner structure of large objects up to kilometers size, since emulsions have firstly an excellent angular resolution, they are compact and robust, do not require power supply. The muonography methods are applied to study one of UNESCO world heritage objects, the unusual building in the Naryn-Kala citadel hidden underground. The use of nuclear emulsions as probing radiation detectors provides for a uniquely high resolution capacity of recording instrumentation combined with the potential of modern image analysis methods giving 3D reconstruction of the internal structures of the investigated object.

The results obtained by measuring the efficiency of detection of charged particles (atmospheric muons) for a prototype of a polyvinyltoluene-based scintillation detector being created for the anticoincidence system of the Signal experiment on board the Interhelioprobe spacecraft are presented. These measurements rely on determining the ratio of the numbers of triple and double coincidences of pulses that arise as atmospheric muons traverse the detector system.

Measurement results of charged particles (atmospheric muon) detection efficiency of a scintillation detector based on polyvinyltoluene, manufactured for the anticoincidence system of the "Signal" device as part of the scientific apparatus for the spacecraft "Interhelioprobe", are presented. The efficiency measurement technique is based on determination of the ratio of triple and double coincidence of the signals arising as atmospheric mu-mesons pass through the system of detectors. The results of light collection simulation in scintillation detectors by the use of Monte Carlo method are presented.

Experiment SIGNAL is planned to take place on board the spacecraft (SC) INTERHELIOPROBE. A xenon gamma-ray spectrometer is to be used in the experiment. The gamma-ray spectrometer in question has been chosen because of its characteristics permitting detailed probing of solar gamma-radiation under rough experimental conditions. The equipment is able to provide: high energy resolution (5-6times better than that of scintillation detectors), goodperformance at high temperatures, steady operation at significant vibroacoustic load, and high radiation resistance of working substance. The aforesaid properties of the xenon gamma-ray spectrometer meet goals and objectives of the experiment SIGNAL.

The results of the calculation of the detection efficiency of gamma-rays for the xenon gamma spectrometer (XGS) obtained using the GEANT4 Monte Carlo simulation are presented. The gamma spectra of the set of basic standard gamma-sources (OSGI) are analyzed for a real detector, and the calculated and actual detection efficiencies are compared. The XGS spectra are analyzed to determine the minimum concentration of the 152Eu radio nuclide in the 137Cs and 60Co mixture. It is shown that the xenon gamma spectrometer is capable of detecting the isotope at concentrations above 40% in the mixture.

A γ-ray detector based on pressurized xenon is described, and the characteristics of the processing of the spectrum of the detector are examined. It is shown that the SpectraLine computer program, where these characteristics are taken into account, makes it possible to process successfully the spectra measured with a pressurized-xenon detector, which greatly expands the possibilities of instruments of this class for performing spectrometric measurements. The possibilities of using pressurized-xenon detectors to solve complex problems of gamma-spectrometric analysis using the GammaLab program system are analyzed. The results obtained show that it is indeed possible, in principle, to use a pressurized-xenon detector together with the SpectraLine computer program for quantitative analysis of samples with a complex radionuclide composition, specifically, to determine the isotopic composition of plutonium.

In the experiment SIGNAL, which is planned to take place on board spacecraft INTERHELIOPROBE, a xenon gammaray spectrometer is to be used. The gamma-ray spectrometer in question has been chosen because of its characteristics permitting detailed study of solar gamma-radiation under rough experimental conditions. The equipment is able to provide: high energy resolution (5-6-fold better than that of scintillation detectors), performance at high temperatures, steady operation under significant vibroacoustic load, and high radiation resistance of the working medium. The aforesaid properties of the xenon gamma-ray spectrometer meet goals and objectives of the experiment SIGNAL. The description of ballistics scenario and operation orbit of the INTERHELIOPROBE spacecraft (SC) are presented.

A method for 222Rn concentration monitoring by means of intensity measurement of its daughter nuclei (214Pb and 214Bi) gamma-ray emission using xenon gamma-ray spectrometer is presented. Testing and calibration results for a gamma-spectrometric complex based on xenon gamma-ray detector are described.

A description of the xenon detector (XD) for gamma-ray line emission registration is presented. The detector provides high energy resolution and is able to operate under extreme environmental conditions (wide temperature range and unfavorable acoustic action). Resistance to acoustic noise as well as improvement in energy resolution has been achieved by means of real-time digital pulse processing. Another important XD feature is the ionization chamber’s thin wall with composite housing, which significantly decreases the mass of the device and expands its energy range, especially at low energies.

Muon radiography is a method of study the internal structure of large natural and industrial objects based on sensing an object with a flux of cosmic muons with their subsequent registration and analysis of the pattern of their dispersion, or conplete (or partial) absorption. The Lebedev Physical Institute of the Russian Academy of Sciences and the Skobeltsyn Institute of Nuclear Physics of Moscow State University have started a series of muon radiography experiments with nuclear emulsion detectors. As a result, the optimal conditions for experiment arrangement have been determined, algorithms of data processing have been worked out, and peculiarities of the method have been ultimately investigated.

Fluxes of electrons and gamma-rays with energies around a few tens of MeV were measured with a balloon-borne detector in November, 1991, in Bauru, (Brazil). The altitude dependences of fluxes and the indices of the differential energy spectra obtained at rigidity 12 GV (Bauru) are compared with results obtained with the same detector at rigidity 3.5 GV in the Volga region (Volsk), Russia.

The principal of design and main characteristics of High Pres- sure Xenon (HPXe) gamma-ray detectors for energy range 0.1-5 MeV are described. High energy resolution of HPXe gamma-ray spectrometers (1.5% at 1 MeV) and availability to manufacture these detectors with dif- ferent sensitive volumes (0.2-10 litres) allow to apply them as for station- ary control portals as for portable inspection detectors. In both cases it is possible not only to register presence of radioactive or fissile materials but also to identify the type of these materials. Numerical tests of HPXe spec- trometers and its application to different tasks have demonstrated their per- spectives as an effective instrument to prevent acts of nuclear/radiological terrorism.

A description of the xenon detector (XD) for ecological applications is presented. The detector provides high energy resolution and is able to operate under extreme environmental conditions (wide temperature range and unfavorable acoustic action). Resistance to acoustic noise as well as improvement in energy resolution has been achieved by means of real-time digital pulse processing. Another important XD feature is the ionization chamber’s thin wall with composite housing, which significantly decreases the mass of the device and expands its energy range, especially at low energies.

The description of the High Pressure Xenon Gamma-Ray Detector (HPXeD) and its main characteristics are considered in the context of the search for hidden fissile materials. The results of HPXeD measurements of gamma-radiation from radioactive sources, which are covered by lead, iron and aluminium shields, are analyzed and discussed. The use of special software for processing data is shown to improve the potential of radioactive material detection, including the identification and estimation of the main protective shield parameters.

Performance of a new modification of xenon gamma-ray detec- tor (XGD) is presented. This detector differs from the previous ones by virtue of improved energy resolution ð1.7 � 0.1Þ% at 662 keV and the ability to function in the presence of external acoustic noise (up to 100 dB) with virtually no degradation of spectrometric characteristics. These results have been achieved by developing a digital method of processing every electric signal coming from the XGD. For this method, digital elec- tronics based on field-programmable gate array has also been developed. © 2014 Society of Photo-Optical Instrumentation Engineers (SPIE) (DOI: 10.1117/1.OE.53.2 .021108)

Construction of cylindrical ionization chamber with shielding mesh is considered. The chamber has sensitive volume 2 liters filled by xenon with pressure about 50 atm. Main characteristics of this detector such as energy resolution and efficiency of gamma-rays with energy 0.1 - 2.0 MeV are presented. It is shown that the detector energy resolution for Eequals0,662 MeV line at optimal electric field strength in the chamber is about 4%. Comparison of experimentally measured characteristics of this detector and standard scintillator NaI(T1) is fulfilled. Applications of the high pressure xenon cylindrical ionization chamber with a shielding mesh in geology, geophysics and diagnostic of oil and gas wells are considered.

The results of xenon detector SIGNAL optimization for gamma-ray bursts (GRBs) detection in satellite experiment “INTERHELIOPROBE” are presented. We have analyzed GRBs temporal profiles and spectral parameters according to Fermi/GBM data and have modeled the xenon detector response, peak count rate and minimum temporal variation intervals for typical events of long, short and intermediate GRBs types. Detector deadtime and optimal ADC channel number had obtained.

In this paper described applicability of xenon gamma detector for identification and characterization of radioactive waste was researched. Standard calibration gamma ray sources were used to determine real physical and technical characteristics of xenon gamma spectrometer. Samples of radioactive waste were measured by xenon gamma detector for identification and characterization.