arXiv subjects

V. D. Ryzhikov

Publications and source records attributed to V. D. Ryzhikov.

9 recordsLinked to original sources

arXiv2008

Detection of organic materials by spectrometric radiography method

In this paper we report a spectrometric approach to dual-energy digital radiography that has been developed and applied to identify specific organic substances and discern small differences in their effective atomic number. An experimental setup has been designed, and a theoretical description proposed based on the experimental results obtained. The proposed method is based on application of special reference samples made of materials with different effective atomic number and thickness, parameters known to affect X-ray attenuation in the low-energy range. The results obtained can be used in the development of a new generation of multi-energy customs or medical X-ray scanners.

physics.ins-det↗

arXiv2004

Application of PbWO4 crystal scintillators in experiment to search for double beta decay of 116Cd

PbWO4 crystal scintillators are discussed as an active shield and light-guides in 116Cd double beta decay experiment with CdWO4 scintillators. Scintillation properties and radioactive contamination of PbWO4 scintillators were investigated. Energy resolution of CdWO4 detector, coupled to PbWO4 crystal as a light-guide, was tested. Efficiency of PbWO4-based active shield to suppress background from the internal contamination of PbWO4 crystals was calculated. Using of lead tungstate crystal scintillators as high efficiency 4-pi active shield could allow to build sensitive double beta experiment with 116CdWO4 crystal scintillators.

nucl-ex↗

arXiv2002

X-ray multi-energy radiography with scintillator-photodiode detectors

For reconstruction of the spatial structure of many-component objects, it is proposed to use multi-radiography with detection of X-ray by combined detector arrays using detectors of ``scintillator-photodiode'' type. A theoretical model has been developed of multi-energy radiography for thickness measurements of multi-layered systems and systems with defects. Experimental studies of the sensitivity, output signal of various inspection systems based on scintillators $ZnSe(Te)$ and $CsI(Tl)$, and object image reconstruction (with organics and non-ogranics materials singled out) have been carried out.

physics.ins-det↗

arXiv2002

Multi-energy radiography on the basis of "scintillator-photodiode" detectors

For reconstruction of the spatial structure and thicknesses of complex objects and materials, it is proposed to use multi-radiography with detection of X-ray or gamma-radiation by combined detector arrays of scintillator-photodiode type. Experimental studies have been carried out of the energy dependence of sensitivity of dual-energy inspection systems based on scintillators $ZnSe(Te)$ and $CsI(Tl)$.

hep-ex↗

arXiv2002

Scintillator-photodiode type detectors for multi-energy scanning introscopy

Results of experimental studies of detector arrays S-PD (scintillator-photodiode) and PRD (scintillator-photoreceiving device) used for X-ray digital radiography have shown that there exist further possibilities to increase spatial resolution of this system up to 2-3 line pairs per mm. Theoretical analysis and experimental studies show that the two-energy detection method not only allows one to detect organics on the background of metal, but also substantially increases (by 3-5 times) the detection ability of the system as a whole, especially if parameters of the S-PD pair are optimized, in particular, when ZnSe(Te) is used in the low-energy circuit. A possibility to distinguish, in principle, between substances with insignificant differences in atomic number has been theoretically proven -- by transition to multi-energy radiography. 3D-imaging has been realized using S-PD detector arrays.

physics.ins-det↗

arXiv2002

X-Ray Multi-Energy Introscopy Systems with New Semiconductor Scintillators

Theoretical background and data on the ways of practical realization are presented, related to the problem of detection of dangerous organic objects (explosives, drugs, etc.) in the presence of other organic substances with atomic number differing by no more than 20-30%. For this purpose, multi-energy X-ray introscopy is used. It has been shown that the "weakest link" in the existing multi-energy introscopes used for safety inspection and medicine are detectors of ionizing radiation. In particular, critical is the type of scintillator used in the low-energy detection subsystem. Data are presented on design principles and properties of combined detectors based on a new type of semiconductor scintillators (SCS) -- $ZnSe(Te,O)$, with conversion efficiency of 19-22%, afterglow level less then $0.05 %$ after $10 ms$, and radiation stability up to $500 Mrad$. Results are given on the practical use of experimental samples of the low-energy detector subsystem based on the new SCS material in two-energy introscopes of the 4th and 5th generation.

hep-ex↗

arXiv2002

Multi-energy techniques for radiographic monitoring of chemical composition

A theoretical model of multi-energy radiography (MER) are proposed. It is shown that, as distinct from the conventional radiography, MER allows identification of organic substances and control of their chemical composition. Broad prospects are noted for MER application, specifically, for detection of prohibited substances (explosives, drugs, etc.) during customs and anti-terrorist safety inspection.

physics.ins-det↗

arXiv2002

Outlook for development of a scintielectron detector with improved energy resolution

The development prospects have been considered of a scintillator-photodiode type detector with improved energy resolution attaining several per cent ($R=1-2%$). The main contributions to the scintielectron detector energy resolution have been analyzed theoretically and their theoretical and physical limits determined. Experimental data have been presented on properties of scintillators of promise confirming the possibilities to minimize each of the resolution components. New ways are proposed to optimize the detector statistical contribution and the scintillator intrinsic resolution. A special role of the latter is outlined as the critical factor for the spectrometric possibilities (threshold) of scintillation-photodiode type detector with improved energy resolution at energy values $E_γ$ from $662 keV$ to $10 MeV$.

hep-ex↗

arXiv2002

Energy Resolution Improvement of Scintielectron detectors: Priorities and Prospects

The development prospects of a scintillator-photodiode type detector with an improved energy resolution attaining few per cent, R from 1 to 2%, are considered. The main resolution components have been analyzed theoretically, their theoretical and physical limits have been established. Empirical data on the properties of novel scintillators have been presented confirming the possibility of the R improvement. New optimization methods have been proposed to optimize the detector statistical fluctuations and the scintillator intrinsic resolution. A specific importance of the intrinsic resolution is shown as a limiting threshold factor at the ionizing radiation energy values from 662 keV to 10 MeV and over.

physics.ins-det↗