Decay Of Isotopes Research Articles

Studies on light, medium, and heavy cluster radioactivity in even-even 300–314122 isotopes

Abstract Using the analytical super asymmetric fission model (ASAFM), we have studied the light ( Z c ≤ 14 ), medium ( 14 < Z c < 28 ), and heavy ( Z c ≥ 28 ) cluster emission from even–even isotopes of superheavy nuclei Z = 122 in the mass region A = 300–314. The predicted half-lives for alpha and light clusters are compared with the predictions using different formalisms, such as the universal decay law (UDL), universal (UNIV) curve, and improved universal (Imp UNIV) curve. It is observed that UDL predictions have the least deviation from ASAFM values. The dip observed in the plot of log 10 T 1 / 2 versus mass number, for alpha decay, at mass number A = 308 highlights the stability of daughter nuclei 304120, which is due to the neutron shell closure at N = 184 and predicted proton shell closure at Z = 120. We have identified isotopes of Sr, Zr, Mo, Cd, In, Sn, etc are the heavy clusters with half-lives comparable to alpha half-lives. The heavy clusters 82Ge, 83As, 84Se, 85Br, 86Kr, etc are also probable for emission from 300–314122. The role of deformed and spherical proton shell closure Z = 38, 40, 50, 82 and spherical neutron shell closure N = 50, 82, 126 of emitted cluster and residual nuclei are evident in heavy cluster radioactivity. The modes of decay of isotopes 300–314122 are analysed by comparing α half-lives and corresponding spontaneous fission (SF) half-lives evaluated by using the improved formula of Yuan et al It is found that the isotopes 300122, 302122, 304122, 306122, and 308122 will survive spontaneous fission and decay via 8α chains, 5α chains, 2α chains, 3α chains, and 1α chain, respectively, which could be of great interest to the experimentalists.

Utilization of traceable standards to validate plutonium isotopic purification and separation of plutonium progeny using AG MP-1M resin for nuclear forensic investigations

Abstract Radio-chronometric studies on plutonium (Pu) materials require independent measurement of the Pu (parent) content and isotopic distribution as well as concentration and isotopic distribution of the plutonium isotopic decay products. We performed a series of experiments to demonstrate the consistency of separations using the Lewatit MP 800 macroporous anion exchange resin and the AG MP-1M resin with traceable Pu isotopic certified reference material (CRM) standards 136, 137, 138, and 126-A. Two different mesh-sizes of the AG MP-1M resin were tested and the 50–100 mesh size resin was found to work more efficiently for the separation task. Both Lewatit and AG MP-1M resins were found to perform satisfactorily for quantitatively extracting the americium (Am) and uranium (U) progeny as well as gallium (Ga) present as a tracer in the Pu material. Both resins were effective in removing isobaric interferences from the Pu fraction used in isotopic measurements by thermal ionization mass spectrometry (TIMS). To address the co-elution of uranium and gallium, Alizarin red S (ARS) was used as a colorimetric dye to determine the behavior of UO2 2+ and Ga3+ on AG MP-1M resin with various acidic solutions as eluents using UV–vis spectra. Poor resolution of these peaks complicated quantitative analysis by UV–vis spectroscopy, but these results were informative in planning automated separation experiments by HPLC. LA-UR-24-28919.

Angular momentum dependence of nuclear decay of radon isotopes by emission of $$^{14}$$C nuclei and branching ratio relative to $$\alpha $$-decay

Angular momentum dependence of nuclear decay of radon isotopes by emission of $$^{14}$$C nuclei and branching ratio relative to $$\alpha $$-decay

Decay Heat Power Uncertainty Quantification in Studsvik’s System for Spent Fuel Analyses

Studsvik’s approach to spent nuclear fuel (SNF) analyses combines isotopic concentrations, fluxes, and cross sections, calculated by the CASMO5 neutron transport and depletion code, with irradiation history data from the SIMULATE5 reactor core simulator and tabulated isotopic decay data. These data sources are used and processed by the SNF code to compute the SNF characteristics. Recent advances in the system, including uncertainty analyses of the computed decay heat power, are presented in this paper. The decay heat power uncertainty is evaluated accounting for the uncertainties in the operating conditions and uncertainties in the nuclear and decay data. The model involves a series of stochastic perturbations combined with the linear propagation law. The uncertainty quantification complements the best estimate decay heat power.

Revolutionizing Age Determination: Theoretical Insights into Radiocarbon (14C) Dating

Radiocarbon dating is a scientific method for determining the age of ancient organic materials, specimens, and artifacts based on the decay of 14C isotopes. This study outlines the mode of formation and assimilation of 14C isotopes in the atmosphere. A traditional carbon-14 dating method estimates sample age by measuring β-ray decay, however, this new technique uses an incredibly sensitive mass spectrometer to count individual carbon-14 atoms in a sample directly. This approach offers several advantages. It eliminates issues related to the cosmic ray background and allows for shorter counting times on much smaller samples, leading to more precise age determinations. Moreover, a wide range of archaeological materials can be dated using milligram-sized samples. Currently, research is underway to develop a specialized machine for counting C-14 atoms, and radiocarbon dating cannot provide exact dates for archaeological or environmental studies on its own. Instead, it needs to use a calibration curve to adjust for changes in atmospheric carbon levels. Any model that proposes the validity of C-14 dating must acknowledge its objectivity and reproducibility. The fundamental principles, methods, and methodology of accelerator mass spectrometry (AMS), and the history, evolution, and revolution in radiocarbon dating techniques are presented in this review.

The Role of Isotopic Geochronology in Earth Sciences

Isotopic geochronology, a specialized field within isotopic geochemistry, has evolved through the interdisciplinary integration of geology, nuclear physics, and radiochemistry. By applying the principles of radioactive isotope decay, isotopic geochronology provides precise geological dating, forming scientific timelines for Earth's major evolutionary stages. This study offers a concise summary and discussion of isotopic dating principles, age representation methods, and the theories, applications, and formulas of widely used high-precision isotopic dating techniques. The primary isotopic dating techniques include: (1) The U-Pb dating method provides four simultaneous age values for a sample. Evaluating their consistency ensures higher reliability in the age determination. (2) The Rb-Sr method, employing isochron techniques, is mainly used for dating mafic, intermediate, and intermediate-acidic igneous rocks, with limited applications in metamorphic and sedimentary rocks. (3) The Sm-Nd method effectively dates mafic and ultramafic rocks and is widely applied in the study of ancient metamorphic rocks' age and genesis. Isochron techniques determine the formation time and initial Nd isotopic values of the source. (4) The Ar-Ar method offers high precision without requiring chemical treatment, thereby minimizing contamination and ensuring complete data integrity. Ages are determined through 40Ar/39Ar ratio analysis. (5) The Re-Os method is directly applicable to ore minerals and extensively used in dating and studying the genesis of metallic ore deposits.

γ‐Ray Driven Aqueous‐Phase Methane Conversions into Complex Molecules up to Glycine

AbstractFundamental understanding of initial evolutions of molecules in the universe is of great interest and importance. CH4 is one of the abundant simple molecules in the universe. Herein we report γ‐ray, high‐energy photons commonly existing in cosmic rays and unstable isotope decay, as an external energy to efficiently drives aqueous‐phase CH4 conversions to various products with the presence of oxygen at room temperature. Glycine also forms with an additional introduction of ammonia. Both CH4 conversions and product distributions are modified by solid granules, and a CH3COOH selectivity as high as 82 % is obtained when SiO2 is added. Our results point to γ‐ray driven aqueous‐phase CH4 conversions as a likely formation network of initial complex organic compounds in the universe and offer an alternative strategy for efficiently utilizing CH4 as the carbon source to produce value‐added products at mild conditions, a long‐standing challenging task in heterogeneous catalysis.

Application of cuttings natural gamma spectroscopy logging technology in well A-1

Abstract The H-1 well revealed significant disparities between the Paleozoic strata in the Northern Jiangsu Basin and the anticipated stratigraphy prior to drilling, posing substantial challenges to the swift determination of stratigraphic ages at the site. Geological logging can obtain very limited data, such as rock color and lithology, and falls short of achieving precise lithologic identification and detailed stratification; while the X-ray diffraction logging(XRD) can initially analyze mineral content, it is unable to delineate the classification of clay mineral species.Cuttings natural gamma spectroscopy logging can precisely analyze the gamma-ray energy spectrum produced by the decay of radioactive isotopes within the formation, primarily comprising potassium, thorium, and uranium.The concentrations of Uranium (U), Thorium (Th), and Potassium (K) in rocks are intimately associate with the lithology, the extent of organic matter content, and the sedimentary environment . This technology facilitates the quantitative assessment of potassium, thorium, and uranium content within the formation. Its application has proven to be crucial for accurately identifying lithologies, conducting detailed stratigraphic comparisons, performing in-depth sedimentary environment analyses, and evaluating organic matter content.The cuttings natural gamma spectroscopy data of H-1 well shows good correlation with the natural gamma logging data, which can meet the requirements of accurate lithology identification; the rocks of different strata in the analytical map can meet the requirements of fine stratum division; the correlation coefficient between U element content and Total Organic Carbon (TOC) content is up to 0.974, which is feasible to calculate the TOC with U element content; finally, the deposition environment analysis based on natural gamma spectral recording confirmed by the analysis of trace elements.

Investigating the impact of gamma irradiation and temperature on vacancy formation and recombination in ZrB2 ceramics using positron annihilation spectroscopy

Investigating the impact of gamma irradiation and temperature on vacancy formation and recombination in ZrB2 ceramics using positron annihilation spectroscopy

Radon Exhalation Rate: A Metrological Approach for Radiation Protection.

Radon, a radioactive inert gas that comes from the decay of naturally occurring radioactive species, poses a substantial health risk due to its involvement in lung cancer carcinogenesis. This work proposes a metrological approach for determining radon exhalation rates from diverse building materials. This methodology employs an electrostatic collection chamber for alpha spectrometry of radon isotopic decay products. Experimental evaluations were conducted particularly focusing on volcanic gray tuff from Sant'Agata de' Goti (Campania region, Italy), a material commonly utilized in construction, to assess radon exhalation rates. The study aligns with Legislative Decree 101/2020, a transposition of European Directive 59/2013/Euratom, highlighting the need to identify materials with a high risk of radon exhalation. Moreover, this work supports the goals of the Italian National Radon Action Plan related to the aforementioned decree, aiming to develop methodologies for estimating radon exhalation rates from building materials and improving radioprotection practices.

A semiclassical model for charge transfer along ion chains in silicates

It has been observed in fossil tracks and experiments in the layered silicate mica muscovite the transport of charge through the cation layers sandwiched between the layers of tetrahedra-octahedra-tetrahedra. A classical model for the propagation of anharmonic vibrations along the cation chains has been proposed based on first principles and empirical functions. In that model, several propagating entities have been found as kinks or crowdions and breathers, both with or without wings, the latter for specific velocities and energies. Crowdions are equivalent to moving interstitials and transport electric charge if the moving particle is an ion, but they also imply the movement of mass, which was not observed in the experiments. Breathers, being just vibrational entities, do not transport charge. In this work, we present a semiclassical model obtained by adding a quantum particle, electron or hole to the previous model. We present the construction of the model based on the physics of the system. In particular, the strongly nonlinear vibronic interaction between the nuclei and the extra electron or hole is essential to explain the localized charge transport, which is not compatible with the adiabatic approximation. The formation of vibrational localized charge carriers breaks the lattice symmetry group in a similar fashion to the Jahn-Teller Effect, providing a new stable dynamical state. We study the properties and the coherence of the model through numerical simulations from initial conditions obtained by tail analysis and other means. We observe that although the charge spreads from an initial localization in a lattice at equilibrium, it can be confined basically to a single particle when coupled to a chaotic quasiperiodic breather. This is coherent with the observation that experiments imply that a population of charge is formed due to the decay of potassium unstable isotopes.

Data reduction strategy in the PandaX-4T experiment

The PandaX-4T experiment is designed for multiple purposes, including searches for solar neutrinos, weakly interacting massive particles, and rare double beta decays of xenon isotopes. The experiment produces a huge amount of raw data that needs to be stored for related physical analyses in a wide energy range. With the upgrading of the PandaX-4T experiment, the doubled sampling rate resulted in a larger data size, which challenges both the cost and the data processing speed. To address this issue, we propose a data reduction strategy by removing the noise tail of large signals and downsampling the remaining parts of them. This strategy reduces the requirement for storage by 65% while increasing data processing speed. The influences on physical analyses on different topics at different energy regions are negligible.

Natural radioactivity of the crust as an important factor of the chemical evolution of the early Earth

Natural radioactivity of the crust as an important factor of the chemical evolution of the early Earth

USING THE IAEA MEDICAL ISOTOPE BROWSER FOR SIMULATION THE PRODUCTION OF IODINE-123

The paper presents the results of modeling the production of a medical isotope using the medical isotope browser of the International Atomic Energy Agency. A web application for the production of medical isotopes allows you to obtain the necessary data on a nuclear reaction based on user data: target radionuclide, irradiating particle or irradiating radiation, energy range, irradiation and cooling time. Tabular values and illustrated graphs of the cross section of the nuclear reaction are obtained based on modeling the production of the isotope iodine-123 from tellurium-124; The isotope decay products are presented. The simulation results were compared with the data recommended by the IAEA for this nuclear reaction for the gamma-emitting radionuclide iodine-123. It is shown that gamma-emitting radionuclide iodine-123 is one of the most convenient radionuclides for single-photon emission computed tomography. When experimental methods are not available, modern technologies in the field of computer modeling allow specialists in a narrow profile to use the achievements of world science to solve problems, in this case, for the production of medical isotopes. Modeling approaches for the production of iodine-123 are recommended for the production of other medical isotopes.

Search for alpha and double alpha decays of natural Nd isotopes accompanied by gamma quanta

Search for alpha and double alpha decays of natural Nd isotopes accompanied by gamma quanta

Selection and purification of Li2CO3 precursor for bolometric double beta decay experiments

This paper describes the preparation of radiopure lithium carbonate powder for the needs of low-background research, in particular, AMoRE-II, the second phase of a search for the neutrinoless double-beta decay (0νDBD) of the 100Mo isotope using over 100 kg of 100Mo contained in 200 kg of ultra-pure Li2100MoO4 bolometric crystals. About 150 kg of pure Li2CO3 powder is required to synthesize the crystals. The desired radiopurity for the lithium powder is 40K below 100 mBq/kg, and Th/U and Ra are at a few mBq/kg. Several commercially available powders were tested with ICP-MS and HPGe detectors at the Center for Underground Physics (CUP) of the Institute for Basic Science in Korea. The lowest purity of the tested products was 99.99%. The results of the powders’ radioassay at CUP showed that none of the tested products were suited for the 0νDBD search application. A special purification technology had to be developed to remove the original contamination of the powder with potassium (K), thorium (Th), uranium (U), and radium (Ra). Lithium carbonate crystallization via carbonization technique was inefficient in removing radiochemical impurities. Lithium formate fractional recrystallization effectively removed Ra, K, and Th, but the synthesis of the final lithium carbonate product had a low yield and required the introduction of additional chemicals. The analysis results of raw and purified powders, the decontamination efficiency, and plans are described in the article.

Applications of First Order Ordinary Differential Equations to Real Life Systems

This article discussed applications of first order ordinary differential equations to real life systems, various types of differential equations with examples are presented. When a dead body is discovered somewhere, Police and detective security agency are eager to identify the time of death and what caused the death. In this article, Newton’s Law of cooling is used to estimate time of death of a dead body discovered in the midnight with the aid of information about the body’s surrounding temperature. It is discovered in this research that Newton’s law of cooling only works when temperature of the body’s surrounding is kept constant. The study also considered other applications of first order differential equations such as population growth model and radioactive decay of radioactive isotopes and illustrative example are given in each case.

Applications of First-Order Ordinary Differential Equations to Real-Life Systems

This article discussed applications of first-order ordinary differential equations to real-life systems, various types of differential equations with examples are presented. When a dead body is discovered somewhere, Police and detective security agencies are eager to identify the time of death and what caused the death. In this article, Newton’s Law of Cooling is used to estimate the time of death of a dead body discovered at midnight with the aid of information about the body’s surrounding temperature. It was discovered in this study that Newton’s law of cooling only works when the temperature of the body’s surroundings is kept constant. The study also considered other applications of first-order differential equations such as the population growth model and radioactive decay of radioactive isotopes and illustrative examples are given in each case.

Assessment of the Geothermal Source Potential Using Aero Radiometric Data in Parts of South-West and South-South, Nigeria

Aeroradiometric surveys have recently become an invaluable resource for geothermal research. The Nigeria Geological Survey Agency (NGSA) provided the airborne radiometric data and other relevant information for the research area. For accurate detection of outliers, we recorded the data at 0.1 second intervals. Geographically, the research region covers the range of longitudes 5.0°E to 6.5°E and latitudes 6.0°N to 7.5°N. Radiogenic heat production (RHP), primarily caused by the decay of uranium, thorium, and potassium isotopes, and the tenary map were the main areas of investigation. We used Rybach’s empirical equation to determine the relative heat production (RHP) by relating the rock’s uranium (Cu), thorium (CTh), and potassium (CK) concentrations. The RHP values of six distinct profiles were calculated over the research area. Due to their higher RHP values (1.028928, 1.031824, and 1.023776 μW/m³, respectively), Profiles 2, 3, and 6 were deemed appropriate geothermal locations. There is a considerable lot of potential for geothermal energy production in Profile 3, which has the highest RHP, as well as in Profiles 2 and 6. Areas with large concentrations of radioactive elements were also shown by the ternary picture and concentration maps, along with regions with notable geothermal gradients and heat flow. Consequently, the regions around Edo State municipalities like as Okada, Okakpan, and Ugboku are ideal for geothermal energy. Geothermal exploration is most effective in areas with large concentrations of radiogenic elements, according to the study’s results, which provide the groundwork for further investigation in these areas.

Experimental and simulation study of a U-shaped water-cooled sleeve heat pipe radiator for high heat flux density

Experimental and simulation study of a U-shaped water-cooled sleeve heat pipe radiator for high heat flux density