The results of testing a xenon gamma spectrometer based on the use of an ionization chamber with compressed xenon are presented. A standard source _27^60Co was used to study the characteristics of the spectrometer. The main characteristics were measured: registration efficiency of 2

The paper investigates the possibility in principle of determining the nuclide composition and activity of gammasources by analyzing the measured gamma-spectra provided an absorber installed between the gamma-sources and a xenon gamma-spectrometer placed in a cylindrical lead collimator.

— The characteristics of the calibration beam of secondary electrons at the Pakhra accelerator based on the SP-3 magnet at the Lebedev Physical Institute are presented. The energy resolution of a beam with a 2-mm-thick copper converter in the electron energy range E = 5–100 MeV is δ ≈ 10%.

Abstract The article focuses on a robotic gamma-ray spectrometric complex designed for decommissioning nuclear and radiation-hazardous objects and monitoring radioactive waste. The complex includes various components, such as radiation monitoring and regular observations to determine the object’s radiation parameters. The control of nuclear and radiation-hazardous objects performed using a High Pressure Xenon gamma-ray spectrometer that installed on a remotely controlled platform.

The paper considers the structure of robotic gamma-spectrometric complexes for the decommissioning of nuclear facilities. It presents physical and technical characteristics of xenon gamma-ray spectrometer considered a key instrument for gamma-ray spectra measurements of analyzed objects and their activity. The study demonstrated the feasibility of xenon gamma spectrometers application in the decommissioning of nuclear facilities. Remotely received information from a gamma spectrometric complex is transmitted via Internet to a remote computer enabling realtime processing of the experimental data.

The structure of gamma spectrometry systems for decommissioning nuclear facilities is considered. Physicotechnical characteristics of a xenon gamma spectrometer being a main device for measuring gamma spectra of analyzed objects and determining their activity are presented. The practicability of xenon gamma spectrometers in decommissioning nuclear facilities is shown. The data obtained using the gamma spectrometry system is transmitted over internet to a remote computer to process experimental data in real time.

The SHiP experiment will search for very weakly interacting particles beyond the Standard Model which are produced in a 400 \GeV/$c$ proton beam dump at the CERN SPS. About $10^{11}$ muons per spill will be produced in the dump. To design the experiment such that the muon-induced background is minimized, a precise knowledge of the muon spectrum is required. To validate the muon flux generated by our Pythia and GEANT4 based Monte Carlo simulation (FairShip), we have measured the muon flux emanating from a SHiP-like target at the SPS. This target, consisting of 13 interaction lengths of slabs of molybdenum and tungsten, followed by a 2.4 m iron hadron absorber was placed in the H4 400~\GeV/$c$ proton beam line. To identify muons and to measure the momentum spectrum, a spectrometer instrumented with drift tubes and a muon tagger were used. During a three-week period a dataset for analysis corresponding to $(3.27\pm0.07)~\times~10^{11}$ protons on target was recorded. This amounts to approximatively 1\% of a SHiP spill.

The description of xenon gamma-ray spectrometers is presented. These devices can be produced with various sensitive volumes (0.2 - 6.0 liters), they provide high energy resolution (similar to 2% at 662 keV) and are capable of operation in unfavorable conditions (wide temperature range and high level of vibro-acoustic influence). Xenon gamma-ray spectrometers can be used for various fundamental and applied tasks, the outcomes of those applications and the prospect of the detector utilization in various fields are also presented.

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.

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.

The paper reports the first test results for detectors of various types and equipment of gamma-spectrometry channels under external radiation originating from pyrochemical reprocessing of spent mixed nitride uranium-plutonium (MNUP) fuel. Testing was carried out on a solid-state detector with a CdZnTe crystal, a scintillation detector with a LaBr3crystal, and an ionization chamber based on compressed xenon. Simulated external gamma-radiation was created by means of a Co-based scattered gamma-radiation source. The paper also describes an experimental facility and a measurement technique, and presents the facility testing results for the above three detectors. The solid-state detector was proved to have the best performance. However, achieving the design characteristics of the gamma-spectrometry channel requires new solutions for protection and collimation of gamma-radiation produced by a real MNUP SNF reprocessing facility. What is meant here is the influence of the detectors’ geometry on the configuration of the protective collimator which is proposed to be used in real conditions. Thus, if a Xe-based detector is used, the calculated mass of the protective collimator is 900 kg, while it is possible to use less massive protection for the other detectors. In addition, when manufacturing neutron shielding for detectors based on CdZnTe and LaBr3, it is necessary to consider the neutron radiation factor in MNUP SNF processing. It is possible to surround the collimator with a moderating layer (for example, polyethylene) and create inside it a skin from a thermal neutron absorber (for example, based on cadmium).

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.

Software tool for gamma-ray spectra analysis was developed. Software tool has the possibilities for visualization of gamma-ray spectra, background and shadow spectrum, analysing of gamma-lines by Gaussian distribution, calculation of gamma-lines characteristics, manipulation with background and shadow spectrum.