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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.

The RED-100 experimental setup, which is designed to detect elastic coherent neutrino scattering off xenon nuclei, is described. One specific feature of this setup is the possibility of using it in above ground experiments. The setup is based on the RED-100 two-phase emission detector in which liquid xenon is used as a working medium for detection of rare events. The results of the technical run with the setup are presented. These are the evidence of the normal operation of all systems and the readiness of the setup for carrying out an experiment.

The intrinsic background of a LaBr3(Ce) scintillator with a diameter of 5 mm and a height of 10 mm has been studied in comparison with LYSO and CeBr3 scintillators. It is shown that due to its high energy resolution the detector based on a LaBr3(Ce) crystal exhibits the lowest background count rate in a specified amplitude range. The measured energy resolution of the detector based on a LaBr3(Ce) crystal with dimensions of O5 mm × 10 mm in combination with a silicon photomultiplier with an active area of 3 × 3 mm2 are presented. It is demonstrated that a detector array with the proposed configuration (a scintillator + a silicon photomultiplier enclosed in a common container) exhibits an energy resolution of 4% for 661.7-keV γ rays and a background count rate of ~0.39 cps in the energy range of (140 ± 3σ) keV.

International audience; The Interhelioprobe mission aims to investigate the inner heliosphere and the Sun from close distances (up to 0.3 AU) and from out of the ecliptic plane (up to 30°). In this paper we present the relevance of the mission and its main scientific objectives, describe the scientific payload, ballistic scenario and orbits of the spacecraft. Possibilities of scientific cooperation with other solar and heliospheric space missions are also mentioned.

The description of gamma-spectrometric apparatus “Nuclide” intended for the detection and identification of elements of radioactive space debris is presented. This device is planned to be installed on the “Universat-SOCRAT” spacecraft. The results of estimations of the sensitivity of this equipment depending on the distance to the objects under study are presented.

The operational orbit of the “Interhelio-Probe” spacecraft is described. The main objectives and missions of the Signal experiment are formulated. The Signal scientific equipment incorporated in this spacecraft is described. Its basic physico-technical characteristics are listed. Operation modes of this equipment onboard the spacecraft are considered.

The thermal stabilization system for the RED-100 liquid-xenon two-phase emission detector has been designed and tested. The RED-100 detector is developed by the Russian Emission Detectors (RED) collaboration for the experiment aimed at detecting the effect of coherent neutrino scattering from xenon nuclei. The system is based on thermosyphons (closed two-phase tubular heat pipes) that are filled with nitrogen and use free-boiling liquid nitrogen pool as a cooling machine. The system is capable of condensing 180-kg liquid xenon sample for 24 h and maintaining the temperature of a titanium cryostat in the range of 160–190 K with a precision about 0.1 K.

Protection of scientific equipment aboard spacecrafts against both natural and artificial constant magnetic fields is an urgent problem. Multilayer film electromagnetic shields produced by electrodeposition showed high shielding efficiency during laboratory tests. To test their application prospects under conditions of real space flights, a “Nanomag” scintillation telescope was developed and fabricated. Laboratory tests which demonstrated its operability at magnetic field induction to 4 mT are presented in this paper.

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 possibility of designing a prototype of the scintillation transition radiation detector (Sci-TRD) based on a thin (∼200 μm) inorganic scintillator has been investigated. Vacuum and silicon photomultipliers have been used in the measurements with inorganic scintillator samples based on LuBO3:Ce and wavelength shifting fibers. The light collection coefficient has been measured for scintillator prototypes under exposure to X rays, and the quantity of photoelectrons has been experimentally determined by irradiating the Sci-TRD working substance with a 241Am X ray source. The electron-hadron rejection ratio of the proposed Sci-TRD is expected to be ∼30.

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.

Photomultiplier tubes (PMTs) are widely used in physical experiments as well as in applied devices. PMTs are sensitive to magnetic field, so creation of effective magnetic shields for their protection is very important. In this paper, the results of measurements of shielding effectiveness of multilayer film magnetic shields on PMT-85 are presented. Shields were formed by alternating layers of a material with high magnetic permeability (Ni-Fe) and high electric conductivity—Cu. The maximum number of bilayers reached 45. It is shown that in weak magnetic fields up to 0.5 mT, the output signal amplitude from PMT-85 does not change for all used multilayer shields. In strong magnetic field of 2–4 mT, the output signal amplitude decrease with 10%–40% depending from the number of layers in the shield. The Pulse distribution of PMT-85 in magnetic field 0.2–4 mT slightly changed in the range 1.1%–1.3% for the case when the number of layers do not exceed 10 and practically did not change for a shield with 45 double layers.

Hi-Cal (High-Altitude Calibration) is a balloon-borne experiment that will be launched in December, 2016 in Antarctica following ANITA-IV (Antarctic Impulsive Transient Antenna) and will generate a broad-band pulse over the frequency range expected from radiation induced by a cosmic ray shower. Here, we describe a device based on an array of silicon photomultipliers (SiPMs) for determination of the azimuthal position of Hi-Cal. The angular resolution of the device is about 3 degrees. Since at the float altitude of ~38 km the pressure will be ~0.5 mbar and temperature ~ − 20 °C, the equipment has been tested in a chamber over a range of corresponding pressures (0.5 ÷ 1000) mbar and temperatures (−40 ÷ +50) °C.

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.

We describe an algorithm for radionuclide detection and identification by the γ-ray spectra recorded with a high-pressure xenon γ-ray spectrometer. The algorithm is based on the comparison of the measured spectra with the tabulated radionuclide data. The fitting criteria were formulated. The software package, implementing the algorithm and providing the execution of a complete cycle of γ-ray spectrum processing, was developed. The algorithm usability and efficiency were demonstrated by testing it with actual spectra.

Software tool "Acquisition and processing of gamma-ray spectra" for xenon gamma-ray spectrometers control was developed. It supports the multi-windows interface. Software tool has the possibilities for acquisition of gamma-ray spectra from xenon gamma-ray detector via USB or RS-485 interfaces, directly or via TCP-IP protocol, energy calibration of gamma-ray spectra, saving gamma-ray spectra on a disk.

In this article the high voltage power supply for xenon spectrometer is described. Result of time simulation for output voltage at different temperatures was shown. The experimental data is confirming results of the time simulations. The experimental data showed breadboard model provides a stability of voltage better than 1% of the generated voltage at different temperatures

Shaping and digital processing of xenon gamma-spectrometer signals were considered. Digital processing influence on the energy resolution of the spectrometric system of xenon gamma-spectrometer was shown. The analysis of contributions to the energy resolution showed that the limit of improvement of the resolution by using of digital processing is reached almost.

A method for earthquake precursors search based on variations of 222Rn concentration determined via intensity measurement of 222Rn daughter nuclei gamma ray emission lines by means of xenon gamma-ray spectrometer is discussed. The equipment description as well as the first experimental data are presented.

In different materials for magnetic shields, the maximum permeability is achieved for different values of the magnetic field. This determines the choice of material. So for protection from magnetic fields strength of 10 - 150 A/m it is advisable to apply the amorphous ribbon 84KXCP. For stronger fields (more than 400 A/m) it is recommended to use MFS based on Ni20Fe80. Use of these materials allows creating an effective shield working in a wide range of magnetic field strengths.

Experimental results of thermal neutrons detection by high pressure xenon gamma- ray spectrometers are presented. The study was performed with two devices with sensitive volumes of 0.2 and 2 litters filled with compressed mixture of xenon and hydrogen without neutron-capture additives. Spectra from Pu-Be neutron source were acquired using both detectors. Count rates of the most intensive prompt neutron-capture gamma-ray lines of xenon isotopes were calculated in order to estimate thermal neutrons efficiency registration for each spectrometer.

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.

Designs of high pressure xenon gamma-spectrometer with high energy resolution is considered. This device is intended for research of space gamma-radiation and space gamma-bursts. It consists of four independent gamma-detectors which are cylindrical ionization chambers with shielding grids. They are filled with high pressure xenon with density 0.5 g/cm3. Working volume of each chamber is 6000 cm3. Energy resolution of the gamma-spectrometer is 2.5% at energy 662 keV and 1.5% at energy 1170 keV. Its sensitive surface equals to 2500 cm2. It is planned to install the developed instrumentation on the scientific power platform of International Space Station.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

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)

The construction of a cylindrical ionization chamber, filled with high pressure xenon (55 bar) is described. The main characteristics of this detector are given. It is shown that the energy resolution of this detector, at 662 keV, is 4% FWHM for the optimal parameters of the gas mixture, applied electric field and shaping time. The detector was tested within a temperature interval between 20°C and 170°C. The dependence of the energy resolution of the cylindrical gamma-ray detector is quite stable. This detector can be used in geology, geophysics, oil and gas well logging.

Gamma-ray background measurements on board the Russian orbital stations Salyut-6, Salyut-7, Mir, Soyuz and Progress have been carried out since 1979. The dependencies of background intensity on mission mass, telescope orientation, and cut-off rigidity are presented for the energy intervals 0.1-8 MeV and 30-600 MeV. The background from man-made sources on board these spacecraft was investigated.

This paper presents a fast approach to simulating muons produced in interactions of the SPS proton beams with the target of the SHiP experiment. The SHiP experiment will be able to search for new long-lived particles produced in a 400~GeV$/c$ SPS proton beam dump and which travel distances between fifty metres and tens of kilometers. The SHiP detector needs to operate under ultra-low background conditions and requires large simulated samples of muon induced background processes. Through the use of Generative Adversarial Networks it is possible to emulate the simulation of the interaction of 400~GeV$/c$ proton beams with the SHiP target, an otherwise computationally intensive process. For the simulation requirements of the SHiP experiment, generative networks are capable of approximating the full simulation of the dense fixed target, offering a speed increase by a factor of $\mathcal{O}(10^6)$. To evaluate the performance of such an approach, comparisons of the distributions of reconstructed muon momenta in SHiP's spectrometer between samples using the full simulation and samples produced through generative models are presented. The methods discussed in this paper can be generalised and applied to modelling any non-discrete multi-dimensional distribution., Comment: 20 pages, 7 figures, amended as per JINST reviewer comments