Development of a method for quantitative comparison of the luminance of self-glowing crystals – the basic elements of a low current source

This work is devoted to the development of a method for the quantitative comparison of the luminosity of weakly luminous samples, such as self-glowing crystals. A self-glowing crystal is an efficient scintillator, whose self-luminescence is due to the decay of a radioactive isotope introduced into the crystal matrix during its growth. Such crystals can be used as low current sources with a service life of 50 years or more. This technique takes into account the luminescence spectra of the samples under study, the spectral functions of the spectrometer and photodetector. Information on the luminescence spectra of samples can be obtained based on their cathodoluminescence spectra. Thanks to the calculations performed according to this technique, it becomes possible to estimate the optical radiation power of a self-glowing crystal, which can be converted into an electric current using a photodiode. Also, the proposed technique can be applied to assess the luminosities of any materials under the influence of radioactive radiation.

Development and evaluation of lead(II) iodide-based polycrystalline digital dosimeter for quality assurance in brachytherapy

Brachytherapy is a cancer treatment that involves intensively irradiating a tumor by placing a sealed radioactive isotope inside the body. Determining the position of the source through accurate quality assurance (QA) is important, because brachytherapy uses radioactive isotope sources with high dose rates. However, in clinical practice, the source position is determined with the naked eye through the use of a ruler, autoradiograph, video monitor, etc., which yields inaccurate results. Therefore, in this study, a lead (II) iodide (PbI2) based polycrystalline digital dosimeter that can measure the relative dose was developed for the QA of the brachytherapy device, and its applicability was evaluated in terms of reproducibility, linearity, percentage interval distance (PID), and angular dependence. Reproducibility evaluation yielded a relative standard deviation value of 1.41%, which satisfied the evaluation criterion of 1.5%. The linearity evaluation yielded an R2 value of 0.9993, which satisfied the evaluation criterion of 0.9990. The PID evaluation revealed that, as the distance from the source increased, the signal decreased according to the inverse-square law. When the PbI2-based digital dosimeter was rotated up to 45°, a difference of up to 13.20% in the angular dependence was observed. Thus, the dosimeter fabricated in this experiment met all the criteria of the aforementioned evaluations. Therefore, it is considered to be highly applicable as a dosimeter for the QA of brachytherapy devices.

Particle identification for neutron rich nuclei ⁶³,⁶⁵Cr from knockout reactions

This paper presents the identification for 63,65Cr isotopes as the products of knockoutreactions for the first time, measured at RIKEN, Japan, within the framework of the “Shell Evolution And Search for Two-plus energies At RIBF” (RIBF- Radioactive Isotope Beam Factory) project, in short SEASTAR. Based on the Bρ-ΔE-ToF method, these nuclei were well separated. The results will be used in the spectroscopic study on 63,65Cr contributing data to the structural study around the N=40 “island of inversion”.

Special Nuclear Material Identification Through One-Minute Measurement with a New Backpack Radiation Device in Real Scenario Conditions

The constant concerns in global nuclear safety, aimed at deterring and combating the illicit trafficking of Material Out of Regulatory Control (MORC) and its possible use in criminal acts has raised the necessity of new detection solutions with higher efficiency and resolution to provide a high level of accuracy in the report to the authorities. Today’s radioactive isotope identifiers perform gamma spectroscopy identification and, sometimes, neutron counting. This paper presents the results of measurements performed in real-scenario conditions with a new type of portable radioactive isotope identifier for the detection and identification of both gamma and neutron sources. Its singular features are: 1) the capability to identify sources through the detection of neutrons, discriminating spontaneous fission sources (Cf-252), α-n sources (Am/Be, Am/Li) and nuclear material containing mix of isotopes of plutonium or uranium 2) the capability to make cross correlation between gamma and neutron measurements to achieve a higher level of accuracy in the identification of SNM that emits both neutrons and characteristics gammas. The test results are compared with international standards. The device exceeds the standard performance by triggering a neutron alarm for a 20.000 n/s Cf-252 source at a five times greater distance than the ANSI N42.34 one.

In situ produced cosmogenic krypton in zircon and its potential for Earth surface applications

Analysis of cosmogenic nuclides produced in surface rocks and sediments is a valuable tool for assessing rates of processes and the timing of events that shaped the Earth surface. The various nuclides that are used have specific advantages and limitations that depend on the time-range over which they are useful, the type of material they are produced in, and not least the feasibility of the analytical effort. Anticipating novel applications in Earth surface sciences, we develop in-situ produced terrestrial cosmogenic krypton (Krit) as a new tool; the motivation being the availability of six stable and one radioactive isotope (81Kr, half-life 229 kyr) and of an extremely weathering-resistant target mineral (zircon). We provide proof of principle that terrestrial Krit can be quantified and used to unravel Earth surface processes.

Determination Radon Concentration (Radon Gas) in Urine of Patients with Cancer

The present study aims at studying the measurement radon concentration (Radon gas) in the urine of patients with cancer, that made up of (23) different samples of patients’ urine. These samples have collected from Kirkuk Oncology & Hematology Center. Chemical etching process for CR-39 track detector has used to record the traces of Alpha particles “alpha rays” or “alpha radiation” that comes from Radon included in the models. The Plastic Tubing – Tubes that contain some models in reagent irradiation process, which shaped as U letter, have been used. The results illustrated that the highest concentration of Radon is (8.9) Bq.m-1 in R14 model, as well as the lowest concentration of Radon is (1.5) Bq.m-1 in R4 model. The Radon levels that have been measured are within the natural limits of radioactive decay caused by radioactive nuclide or “radioactive isotope” in urine of patients with cancer; these are not a risk in humanity.

An overview of some dating methods of mineralization

One of the most important achievements of applying radioactive isotope in the geological study is to determine the age of mineralization. Based on the synthesis, comparison, and evaluation of the popular isotopic systems in dating mineralization, the Rb - Sr, Re - Os, and Ar - Ar dating methods are discussed in this study. The results show that the Rb - Sr dating method is likely to be successfully applied to sulfide mineralization. If the mineralization contains little or no sulfide minerals, then the method is applied to other minerals in an ore mineral association. The Re - Os dating method has shown great success when it is applied to hydrothermal deposits, especially for the molybdenite - bearing vein deposits. The limitation of the method is that when the concentration of the Os element in molybdenite is low, it is difficult to establish the Re/Os ratio in a single mineral. The Ar - Ar isotope system for dating mineralization often uses mica or feldspar minerals, which are minerals with blocking temperatures ranging from 150÷350 0C, and later metamorphic periods have higher than 350 0C often overprinted these minerals. Generally, tectonic, magmatic, and metamorphic events, which occur after mineralization, can cause difficulty in determining the age of mineralization and collecting analysis samples.