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Purpose: To ensure comparable PET/CT image quality between or within centres, clinical inter-system performance comparisons following European Association of Nuclear Medicine Research Ltd. (EARL) guidelines is required. In this work the performance of the long axial field-of-view Biograph Vision Quadra is compared to its predecessor, the short axial field-of-view Biograph Vision. Procedures: To this aim, patients with suspected tumour lesions received a single weight-based (3 MBq/kg) 2-deoxy-2-[18F]fluoro-D-glucose injection and underwent routine clinical (∼ 15 min) scans on the Vision and 3-min scans on the Quadra in listmode in balanced order. Image quality (IQ), image noise (IN), and tumour demarcation (TD) were assessed visually by four nuclear medicine physicians using a 5-point Likert scale and semiquantitative analysis was performed using standardised uptake values (SUVs). Inter-reader agreement was tested using Wilcoxon's signed rank test and the SUVs were statistically compared using a paired t-test. Results: Twenty patients (mean age, 60 years ± 8.8 [standard deviation], 16 male) were enrolled. Inter-reader agreement ranged from good to very good for IQ and IN (0.62 ≤ W ≤ 0.81), and fair for TD (0.29 ≤ W ≤ 0.39). Furthermore, a significant difference was found for TD (p = 0.015) between the systems, showing improved TD for the Quadra. Conclusion: This study demonstrates that the Quadra can be used in routine clinical practice with multiple PET/CT systems or in multicentre studies. This system provides comparable diagnostic image quality and semiquantitative accuracy, improved TD, and has the advantage of shorter scan durations. [ABSTRACT FROM AUTHOR]

Extensive nuclear data studies have been carried out over the last 30 years in the context of accelerator-based production of radionuclides, especially at energies below 30 MeV, and the achieved database is fairly good. Yet there are some deficiencies or new needs of data. Those needs are generally associated with new emerging clinical applications of radionuclides, e.g. theranostic approach, bimodal imaging, radioimmuno-therapy, etc. This article gives an overview of on-going nuclear data research utilizing charged-particle accelerators in four directions, namely low-energy region, intermediate energy range, use of the α-particle beam, and utilization of fast neutrons generated at accelerators. Wherever possible, a comparison of experimental data with theoretical estimates is presented and evaluated (standardised) data, if available, are also briefly discussed. [ABSTRACT FROM AUTHOR]

This special issue of the European Physical Journal: Special Topics focuses on the study of nuclear isomers, which are long-lived excited states of atomic nuclei that can store significant amounts of energy. The issue covers various topics related to nuclear isomerism, including theoretical origins, decay mechanisms, and their role in understanding shell evolution and symmetries in nuclei. The preface highlights the importance of studying isomer physics and mentions potential applications in energy storage, nuclear photonics, and nuclear medicine. The authors express gratitude to the contributors and funding agencies that supported the publication of the special issue. [Extracted from the article]

Nuclear isomers, the excited meta-stable states of nuclei, offer profound insights into nuclear structure. This article reviews the intersection of nuclear isomer research with mass spectrometry methodologies, particularly focusing on novel capabilities of the multiple-reflection time-of-flight mass spectrometry (MR-TOF-MS) technique. Through a comprehensive examination of established methods for isomer identification and characterization, alongside the technical principles underlying MR-TOF-MS, this review discusses the pivotal role of mass spectrometry in advancing our understanding of nuclear isomers. The operational principles and recent developments in MR-TOF-MS technology are explained and exemplified through case studies from prominent research facilities. Furthermore, this work discusses ongoing efforts to enhance sensitivity, resolution, and measurement capabilities in MR-TOF-MS, promising continued advancements in nuclear physics research and applications. [ABSTRACT FROM AUTHOR]

The study of nuclear isomer properties and the isomer applications is a current research focus of nuclear physics and nuclear astrophysics. Theoretical description of nuclear isomers, the surrounding states, and the interplay of them becomes an important issue. In this article, we present the projected shell model method for describing excited nuclear states in general, and for treating K-isomers in particular. With some examples, we emphasize how to apply the modern nuclear many-body technique to calculate K-isomers and normal excited states on an equal footing. [ABSTRACT FROM AUTHOR]

To study the dependence of the equation of state of high-density nuclear matter on the term characterizing the isospin (proton–neutron) asymmetry of nuclear matter, it is necessary to measure azimuthal flow of neutrons as well as azimuthal flow of charged particles from a dense nuclear matter in the nuclear–nuclear collisions. For this purpose, the Institute for Nuclear Research (Russian Academy of Sciences) is developing a new high-granular neutron detector that will be used in the BM@N experiment at the extracted beam of the Nuclotron accelerator at the Joint Institute for Nuclear Research (JINR, Dubna). This detector will identify neutrons and measure their energies in the heavy-ion collisions up to 4 GeV per nucleon. This article presents the results of measurements of the time resolution and light yields of samples of scintillation detectors with sizes 40 × 40 × 25 mm3 that will be used in a neutron detector based on the currently available fast plastic scintillator manufactured by JINR using an EQR15 11-6060D-S photodetector for light readout. For comparison, the results of measurements for a detector of the same size with a EJ-230 fast scintillator and with the same type of photodetector are given. The measurements were made on cosmic muons as well as on the Pakhra electron synchrotron of the Lebedev Physical Institute of the Russian Academy of Sciences located in Troitsk, Moscow. [ABSTRACT FROM AUTHOR]

The present work deals with diffusion of gases in fully saturated porous media. We test and validate the gas transport mechanism of dissolution and diffusion, implemented in the TH2M process class in the open-source finite-element software OpenGeoSys. We discuss the importance of gas diffusion for the integrity of the multi-barrier system. Furthermore, we present a multi-component mass balance equation implementation in Python, which serves as a reference for the two-component TH2M implementation and allows for a discussion of multi-component gas diffusion in liquids. We verify and validate the numerical implementations as follows: First, we come up with a set of numerical benchmarks in which solutions obtained by the two-component TH2M and multi-component implementations are compared. Thus, we show under which conditions predictions made by the TH2M model can be used for multi-component gas systems. Finally, the work is validated using a through diffusion experiment performed at Belgium's Nuclear Research Centre SCK CEN and a sensitivity analysis is conducted based on the featured experiment. The results of this work illustrate that predictions by both the two- and four-component models match the laboratory findings very well. Therefore, we conclude that also the two-component implementation can reflect the multi-component processes well under the given constraints such as full saturation. Highlights: Numerical modelling of a laboratory scale gas diffusion experiment using Boom Clay samples. Validation of numerical implementation by comparison of experimental and numerical results. Extension of a two-component two-phase flow model towards a multi-component model including comparison of the two implementations. Sensitivity analysis identifies and quantifies the influence of key diffusion parameters, such as the Henry coefficient and diffusivity. [ABSTRACT FROM AUTHOR]

The nuclear dd-fusion reaction can proceed by three possible channels: , , . Interest in dd-fusion has been aroused by both fundamental research and astrophysics and applied science, particularly in the field of fusion reactor development. In the 1970s, the idea of studying the nuclear dd-fusion reaction using polarized deuteron beams was proposed at the Kurchatov Institute. The development of this idea was continued in the PolFusion (polarized fusion) nuclear physics experiment, which aims at studying the reaction of nuclear dd synthesis with polarized source particles in the low energy region. The experiment is planned to measured the scattering asymmetries of dd-fusion reaction products in the final state at different mutual orientation of the spins of colliding deuterons in the energy range 10–100 keV. The authors present an overview of the status of the experiment. [ABSTRACT FROM AUTHOR]

Initially, the growth of particle detectors was focused on the identification of particles, but new detector designs have made it possible to build new diagnostic techniques. Clinical settings and medical research facilities utilize cutting-edge methods developed from particle accelerators, detectors, and physics computers, including imaging technologies, accelerators specifically designed for cancer therapy, simulations, data analysis, and nuclear medicine. It is still obvious that research in nuclear and basic particle physics is what motivates and propels the development of particle detectors for medical applications. The applications of the particle physics detector in medical science will be the main topic of this paper. [ABSTRACT FROM AUTHOR]

Autonomous nuclear reactor monitoring is a key aspect of the International Atomic Energy Agency's strategy to ensure nonproliferation treaty compliance. From the rise of small modular reactor technology, decentralized nuclear reactor fleets may strain the capacities of such monitoring and requires new approaches. We demonstrate the superior capabilities of a gamma detection system to monitor the criticality of a zero power nuclear reactor from beyond typical vessel boundaries, offering a powerful alternative to neutron-based systems by providing direct information on fission chain propagation. Using the case example of the research reactor CROCUS, we demonstrate how two bismuth germanate scintillators placed outside the reactor vessel can precisely observe reactor criticality using so called noise methods and provide core status information in seconds. Our results indicate a wide range of applications due to the newly gained geometric flexibility that could find use in fields beyond nuclear safety. [ABSTRACT FROM AUTHOR]

The work investigated the sorption of no-carrier-added 177Lu isolated from neutron-irradiated 176Yb2O3, and carrier-added 177Lu obtained by irradiation of natLu2O3, by commercial and oxidized nanodiamonds (NDs) of various grades from aqueous solutions to identify among them a promising carrier for further research in the field of nuclear medicine. A promising sorbent was found: oxidized NDs of the STP grade (ox-STP); conditions for the fast sorption of lutetium with it in an amount equivalent to 1.2 GBq of no-carrier-added 177Lu were determined, which corresponds to the activity used in therapy. [ABSTRACT FROM AUTHOR]

Background: Accurate image-derived input function (IDIF) from highly sensitive large axial field of view (LAFOV) PET/CT scanners could avoid the need of invasive blood sampling for kinetic modelling. The aim is to validate the use of IDIF for two kinds of tracers, 3 different IDIF locations and 9 different reconstruction settings. Methods: Eight [18F]FDG and 10 [18F]DPA-714 scans were acquired respectively during 70 and 60 min on the Vision Quadra PET/CT system. PET images were reconstructed using various reconstruction settings. IDIFs were taken from ascending aorta (AA), descending aorta (DA), and left ventricular cavity (LV). The calibration factor (CF) extracted from the comparison between the IDIFs and the manual blood samples as reference was used for IDIFs accuracy and precision assessment. To illustrate the effect of various calibrated-IDIFs on Patlak linearization for [18F]FDG and Logan linearization for [18F]DPA-714, the same target time-activity curves were applied for each calibrated-IDIF. Results: For [18F]FDG, the accuracy and precision of the IDIFs were high (mean CF ≥ 0.82, SD ≤ 0.06). Compared to the striatum influx (Ki) extracted using calibrated AA IDIF with the updated European Association of Nuclear Medicine Research Ltd. standard reconstruction (EARL2), Ki mean differences were < 2% using the other calibrated IDIFs. For [18F]DPA714, high accuracy of the IDIFs was observed (mean CF ≥ 0.86) except using absolute scatter correction, DA and LV (respectively mean CF = 0.68, 0.47 and 0.44). However, the precision of the AA IDIFs was low (SD ≥ 0.10). Compared to the distribution volume (VT) in a frontal region obtained using calibrated continuous arterial sampler input function as reference, VT mean differences were small using calibrated AA IDIFs (for example VT mean difference = -5.3% using EARL2), but higher using calibrated DA and LV IDIFs (respectively + 12.5% and + 19.1%). Conclusions: For [18F]FDG, IDIF do not need calibration against manual blood samples. For [18F]DPA-714, AA IDIF can replace continuous arterial sampling for simplified kinetic quantification but only with calibration against arterial blood samples. The accuracy and precision of IDIF from LAFOV PET/CT system depend on tracer, reconstruction settings and IDIF VOI locations, warranting careful optimization. [ABSTRACT FROM AUTHOR]

In the course of the program for the development of high-resolution photographic materials for research in neutrino physics, the possibility of obtaining a nuclear emulsion with a resolution that exceeds the known materials by 5 times has been shown. The sensitivity in such materials is maintained at a high level, sufficient for the registration of nuclear radiation. With an increase in the concentration of silver halide up to 80 wt %, nuclear photographic materials can be used to solve many physical problems. [ABSTRACT FROM AUTHOR]

The concentrations of the gases 12CO2, 13CO2, СН4, and Н2О and the trends of Earth degassing under changing atmospheric pressure were analyzed remotely for the first time using a differential absorption lidar. To reduce the influence of external meteorological factors, the sensing was carried out in a dead-end tunnel of the Baksan Neutrino Observatory of the Institute for Nuclear Research, Russian Academy of Sciences. [ABSTRACT FROM AUTHOR]

This work is mainly concerned with the effect of anthropogenic activities and natural radioactivity due to the presence of highly radioactive black sand spots, factory construction, and shipping, in addition to other activities like agriculture on human beings. Forty samples were collected along Baltim–El Burullus coastal plain to detect the effect of these problems and determine the suggested solutions. The black sand of the Baltim–El Burullus coastal plain exhibits a considerable amount of economically heavy minerals, their ratio relative to the bulk composition in the investigated samples ranges from 3.18 to 10.5% with an average of 5.45%. The most important of them are magnetite, ilmenite, rutile, leucoxene, garnet, zircon and monazite. The existence of some radioactive-bearing accessory mineral deposits like zircon and monazite led to measuring the naturally occurring radionuclides 226Ra, 232Th and 40K to evaluate the excess lifetime cancer risk (ELCR). The results showed that these concentrations are 19.1 ± 9.73, 14.7 ± 9.53 and 211 ± 71.34 Bq kg−1 were lower than the corresponding reported worldwide average of 35, 45, and 412 Bq kg−1 for each radionuclide (226Ra, 232Th, and 40 K). The gamma hazard indices such as absorbed dose rate (Dair), the annual effective dose (AED), and excess lifetime cancer risk (ELCR) factor were computed in the investigated sediments and all the results were found (Dair = 26.4 nGy h−1, AED = 0.03 mSv year−1, ELCR = 0.0001) to be lower than the values suggested by the United Nations Scientific Committee on the effect of Atomic Research (59 nGy h−1, 0.07 mSv year−1 and 0.0029 for Dair, AED and ELCR, respectively). The study suggests that the black sand is safe to use in various infrastructure applications at Baltim–El Burullus coastal plain. The levels of radioactivity are not high enough to pose a risk to human health. [ABSTRACT FROM AUTHOR]

The conventional nuclear medical imaging, such as PET and SPECT, visualizes the accumulation of radioisotopes in the human body and has been widely used for diagnosis of cancer and other diseases. Perturbed angular correlation is a powerful sensing tool detecting local electro-magnetic environment and has been used for chemical analysis or nuclear physics research. The use of perturbed angular correlation in nuclear medicine is recently proposed and pH sensing capability with liquid 111 In has been confirmed. In more practical applications, DOTA based radioisotope labeled drug delivery is common in nuclear medicine. This study aims to characterize the pH dependance of perturbed angular correlation in Psyche-DOTA chelated 111 In with the custom ring-shape gamma-ray detectors. The observed transition in anisotropy of cascade gamma-ray emission can contribute to the detection of a specific phenomenon changing pH inside the human body. [ABSTRACT FROM AUTHOR]

β -detected nuclear magnetic resonance (β -NMR) is a powerful research tool in nuclear physics and material sciences. In this study, we integrated an imaging function into a β -NMR instrument. Specifically, we installed position-sensitive detectors to create a magnetic resonance imaging device, which we have named the β -MRI. We conducted experiments to evaluate the performance of this device by irradiating spin-polarized 12 B beams on a sample, and successfully generated its material mapping image. [ABSTRACT FROM AUTHOR]

Abstract—The article considers the efficiency and possibility of introducing into operation of VVER-1000 power units with the lifetime extended owing to the sliding pressure of the second circuit. The history of research by Russian nuclear engineers on VVER lifetime extension is reviewed. It is shown that reduction of fresh steam pressure within the allowed limits will make it possible to release additional reactivity through release of the temperature effect and to generate additional energy during the period of unit operation on the power effect. A mathematical model of changes in the main parameters of the reactor unit, including reactivity balance equations, Stodola–Flugel equation for the turbine, and heat balance and heat transfer equations in the steam generator, is compiled. The expected increase in power generation for modern fuel loadings of VVER-1000 reactors is calculated. The degree of compliance of the proposed mode with the current technological limitations of the large-series VVER-1000 power units is analyzed. The results of the analysis are confirmed by the numerical experiment on the multifunctional analyzer of the VVER-1000 unit modes developed by the National Research Nuclear University MEPhI built on the basis of the ENICAD environment and the certified diffusion neutronic code PROSTOR. Conclusions are drawn about the possibility of introducing the proposed mode into the operational practice of modern VVER-1000 power units. [ABSTRACT FROM AUTHOR]

The structure of a compact X-ray source based on inverse Compton scattering and the beam dynamics in the linac and the storage ring is considered. The features of collective effects in the storage rings of such installations are studied in compaаrison with fourth-generation SR sources. The thresholds of longitudinal microwave instability and transverse instability of coupled modes are calculated. [ABSTRACT FROM AUTHOR]

OpenMC is a state-of-the-art Monte Carlo neutron transport simulation code that uses the Python programming language as an API. OpenMC supports eight burnup simulation algorithms. This study presents the results of choosing an integration method for modeling the burnup of fuel assemblies with burnable poisons for VVER-1000 reactors. Burnup simulation results from OpenMC were compared with those reported in the OECD benchmark. Eight different numerical integrators can be used to model burnup in the OpenMC code: PI, CE/CM, LE/QI, CE/LI, CF4, EPC-RK4, SI-CE/LI, SI-LE/QI. The test results showed that the SI-CE/LI and SI-LE/QI integrators require significantly more time to calculate one burnup step than the others with the same accuracy, so they were excluded from further consideration. The PI integrator showed low integration accuracy at the same burnup steps with other integrators. However, PI has a high performance compared to other integrators, and as the integration step decreases, it converges to one solution, which can be chosen as a reference for assessing the quality of other integrators. On the basis of the results obtained using the fine step PI integrator, it was decided to use the CE/LI integrator for further work. The results obtained with CE/LI were compared with those obtained with the VVER-1000 LEU and MOX benchmark for the codes MCU, TVS-M, WIMS8A, HELIOS, and MULTICELL and showed good agreement. Thus, we can conclude the applicability of the CE/LI integrator as part of OpenMC for modeling the burnup of fuel assemblies containing burnable poisons. During the work, the resources of the high-performance computer center of the National Research Nuclear University MEPhI were used. [ABSTRACT FROM AUTHOR]

Results of calculations of the electrodynamic characteristics of short five-gap accelerating cavities of the IH type are presented. The cavities are designed for a linear accelerator of protons and light ions with a charge-to-mass ratio A/Z ranging from 1 to 3.5. Developed at National Research Nuclear University MEPhI, this accelerator, which is designed as a source of charged particles with a beam energy of 7.5 MeV/nucleon, is intended for basic and applied research. The issues of the complex influence of the geometry of the drift tubes and the geometry of the drift tube support on the magnitude of the field strength on the surface of the resonators, the power losses in the walls of the resonators, and the distribution of the accelerating field on the axis are considered, taking into account the influence of the accuracy of segmenting in simulation. [ABSTRACT FROM AUTHOR]

Project of a specialized mass spectrometer for precision mass measurement of superheavy elements at the Factory of Superheavy Elements at the Joint Institute for Nuclear Research (JINR) in Dubna is presented in the paper. The mass spectrometer is intended for achieving the mass accuracy of 10–7 at a low statistics (~5 events). The key part of the mass spectrometer is a new generation multi-reflection time-of-flight mass analyzer. To prepare and separate the probe and calibrant, a set of new ion-optical elements is implemented in the spectrometer, such as a radio-frequency selector of the state of charge, quadrupole mass filters operating in the beat node coincidence mode, a collision dissociation cell with beam focusing in the gap of a vacuum valve, and a source of calibration ions with electron ionization of fullerene soot. [ABSTRACT FROM AUTHOR]

An experimental facility has been developed by MEPhI to study the spectrometric characteristics of gas mixtures for cascade gas electron multipliers (GEMs), which are widely used in modern tracking, Cherenkov, and synchrotron-radiation detectors designed for high-energy physics experiments. The characteristics of the gas mixture for the GEMs used in the BM@N international experiment (Joint Institute for Nuclear Research, Dubna) have been investigated. The applicability of this facility for laboratory works accompanying the Nuclear Physics and Technology master's courses is noted. [ABSTRACT FROM AUTHOR]

The origin of cosmic rays can be deciphered by accurately measuring the components and energy spectrum in the knee region. Study of Extensive air shower (EAS) relies on information provided by secondary high energy hadrons, which generate evaporation neutrons when they interact with matter in the environment. In the early 21st century, the electron–neutron detector (EN-detector) was developed at the Institute for Nuclear Research of the Russian Academy of Science (INR RAS). The PRImary Spectrum Measurement Array (PRISMA) project was introduced to enhance the array capabilities of cosmic ray composition separation and improve measurement accuracy. Within the framework of Chinese–Russian cooperation, at the Large High Altitude Air Shower Observatory (LHAASO) at Mt. Haizi (4400 m a.s.l.) in Daocheng, Sichuan province, China, a proposal was launched to establish the EN-Detector Array (ENDA) composed of 400 detectors in area of 10000 m to measure cosmic rays up to 300 PeV. In China, in 2018, a cluster, having 16 EN-detectors, was built at Tibet University (TU, 3700 m a.s.l.) in Lhasa, Tibet, to test specification of the array, and later it was moved to the Yangbajing (YBJ) Cosmic Ray Observatory (4300 m a.s.l.) in Tibet. Since 2019, another cluster so called ENDA-16 has started running at LHAASO, and here we give the first result of thermal neutron distribution. After gaining experience from these previous works, in April 2023, we successfully extended ENDA to ENDA-64 composed of 64 EN-detectors in area of 1000 m at LHAASO to measure cosmic rays from 400 TeV to 20 PeV. Here we describe installation and running status of ENDA-64 and present first results of thermal neutron distributions at different locations and hybrid detection of cosmic ray by using ENDA and LHAASO. [ABSTRACT FROM AUTHOR]

The research works of Professor Michael Brunger have spanned a period of more than 40 years. In this paper, we set out to record his contributions in the field of Atomic and Molecular Physics by using a bibliometric analysis approach. Firstly, we give an overview of his publication and citations, and we highlight his top 10 cited papers and their impact in this field of research. Secondly, we explore the diversity of his research areas in general. Finally, we perform an analysis of his research collaborations with international groups with clear visualization. We have used a wide range of bibliometric indicators: citation indicators; indices of structural difference; indicators of scientific collaboration. [ABSTRACT FROM AUTHOR]

In this manuscript, production of 201TlCl, one of the radiopharmaceuticals used in the field of nuclear medicine for diagnostic purposes in heart, muscle, thyroid gland imaging, and cancer diagnosis, at Turkish Energy Nuclear and Mineral Research Agency is described. The production process starts with a cyclotron type proton accelerator operated in energy range of 15–30 MeV with beam intensities up to 1200 μA currently available at the facility. The production is detailed along with the main lines in the other steps. In addition to the radiopharmaceutical productions carried out according to international standards at the facility, new projects are planned in the short and long terms. [ABSTRACT FROM AUTHOR]

The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) is the world's largest and most powerful particle accelerator colliding beams of protons and lead ions at energies up to 7 Z TeV, where Z is the atomic number. ALICE is one of the experiments optimised for heavy-ion collisions. A fixed-target experiment in ALICE is being considered to collide a portion of the beam halo, split using a bent crystal inserted in the transverse hierarchy of the LHC collimation system, with an internal target placed a few metres upstream of the existing detector. This study is carried out as a part of the Physics Beyond Collider effort at CERN. Fixed-target collisions offer many physics opportunities related to hadronic matter and the quark-gluon plasma to extend the research potential of the CERN accelerator complex. Production of physics events depends on the particle flux on the target. The machine layout for the fixed-target experiment is developed to provide a flux of particles on the target high enough to exploit the full capabilities of the ALICE detector acquisition system. This paper summarises the fixed-target layout consisting of the crystal assembly, the target and the downstream absorbers. We discuss the conceptual integration of these elements within the LHC ring, the impact on ring losses, and expected performance in terms of particle flux on target. [ABSTRACT FROM AUTHOR]

The results of the studies of ferroelectric, ferroelastic, and superprotonic crystals, performed by the researchers from the laboratory headed by L.A. Shuvalov at the Institute of Crystallography of the Russian Academy of Sciences and the Laboratory of Neutron Physics of the Joint Institute for Nuclear Research, using methods of neutron diffraction and inelastic scattering, are briefly reviewed. The main results in this field were obtained in the period from the end of the 1970s to the end of the 1990s. [ABSTRACT FROM AUTHOR]

This work presents results of the first tests of machine learning application using gradient boosting on oblivious decision trees to particle identification problem in Multi Purpose Detector (MPD) experiment on Nuclotron based Ion Collider fAcility (NICA) at Joint Institute for Nuclear Research. Categorical boosting (CatBoost) implementation of a gradient boosting on decision trees has been used. Particle identification was based on the information provided by the time projection chamber (TPC) and the time-of-flight (TOF) subdetectors. In the study three various Monte-Carlo datasets of measurements from TPC and TOF were simulated and used within CatBoost classifiers training and testing. The comparison was made with the -sigma method which is currently used at MPD software. Gradient boosting shows better efficiency in case of small and large momentum values ( GeV and GeV ). This demonstrated that machine learning methods are well suited to address the particle identification problem in MPD experiment. [ABSTRACT FROM AUTHOR]

This research presents a synthesis process of porous α-MoO3 wire from Mo wire and its application as an irradiation target used in the Dalat Nuclear Research Reactor (DNRR) for the first time. Water was used to extract 99Mo in the porous wire after irradiating, afterward, the result was compared with a previous experiment using α-MoO3 powder. In conclusion, combined with the Kyoto University Reactor (KUR) experiments, hot atoms ehnanced the extraction of 99Mo to water and the effectiveness in the porous wire was compared to that of commercial powder. [ABSTRACT FROM AUTHOR]

We propose a system to produce multiple spin reversals of a polarized proton beam based on orbit-steerer dipoles already installed in the Nuclotron, a superconducting synchrotron at the Joint Institute for Nuclear Research, when the latter operates in the spin-transparency regime. The beam momentum of 3.54 GeV/c corresponds to the integer spin resonance . We report the results of numerical simulation of the proton spin dynamics pertinent to the acceleration up to , including the adiabatic capture of spins by navigators and the subsequent multiple spin flips. A feasibility of the pilot experiment to verify our approach with the current magnetic lattice of the Nuclotron is discussed. To preserve the beam polarization during the crossing of integer resonances we propose to employ intentional resonance-strength enhancements effected by controlled variations of the beam orbit during acceleration. [ABSTRACT FROM AUTHOR]

Prof. Hyunjoo Lee is a Full Professor in the Department of Chemical and Biomolecular Engineering at the Korea Advanced Institute of Science & Technology (KAIST), Korea, and a KAIST Endowed Chair Professor. She also serves as the Director of the Heterogeneous Atomic Catalysts Research Center. [ABSTRACT FROM AUTHOR]

A new compact time-of-flight neutron detector is being planned for the identification and energy measurement of neutrons produced in nucleus-nucleus interactions at energies up to 4 AGeV at the BM@N experiment, located at the Nuclotron (Joint Institute for Nuclear Research, Dubna, Russia). This detector will be used to measure neutron yields and azimuthal flows, which should be sensitive to the equation of state of dense nuclear matter, as shown in various theoretical models It is proposed to use plastic scintillators produced at JINR and IFTP and silicon photomultipliers with a sensitive area of 6 × 6 mm2 for photon registration, one for each scintillation cell. To achieve the required neutron energy resolution (of the order of several percent) in the energy range up to 4 GeV, the time resolution of scintillation detectors should be 100−150 ps. The concept of a time-of-flight neutron detector is discussed. The results of measurements of the light yield and time resolution of several scintillation detector specimens of various sizes and two types of silicon photomultipliers are presented. [ABSTRACT FROM AUTHOR]

The Algerian NAA laboratory at the Nuclear Research Centre of Birine participated in the framework of PTNAT-IAEA project organized by IAEA. This paper presents the results of the proficiency tests performed during 2021–2022 by using k0-NAA method. The analytical work is based on the determination of major, minor and trace element in a sandy soil sample (PTNATIAEA/18) 2021 and clay sample (PTNATIAEA/19) 2022. The measurand mass fraction of 28 elements have been determined by using k0-NAA technique. The statistical parameters z-score and zeta score established in full compliance with ISO 13528 have been evaluated and good agreement is achieved. [ABSTRACT FROM AUTHOR]

New values of neutron fluxes and spectral parameters f and α were determined experimentally in all irradiation devices of the TRIGA Mark I IPR-R1 nuclear research reactor at Nuclear Technology Development Centre (CDTN), Belo Horizonte, Brazil. Sets of monitors Au, Fe, Zn and Zr were irradiated bare and Cd-covered, according to "Cd-ratio for multi-monitor" method. Values were validated by analysing the certified reference material BCR-320R irradiated in chosen channels. The calculations were made based on irradiation channel values and the average values of the Carousel. The results of En-score point out that the k0-method is producing reliable results. From now on, the values of mass fractions in several matrices, the production and studies with radioisotopes will be more accurate and the activities calculated more precisely. [ABSTRACT FROM AUTHOR]

At present, powder materials are used in almost all known branches of science and technology such as the automotive industry and metalworking, medicine and nuclear research. This is a wide range of structural and tool materials, and special-purpose materials that have good heat resistance, wear resistance, and resistance within corrosive media. Ultrafine powders are used extensively in development of new functional materials and nanomaterials, since an increase in the discrete nature of structural elements leads to a significant change in material properties. [ABSTRACT FROM AUTHOR]

Purpose : Monoclonal antibody (mAb)-based PET (immunoPET) imaging can characterise tumour lesions non-invasively. It may be a valuable tool to determine which patients may benefit from treatment with a specific monoclonal antibody (mAb) and evaluate treatment response. For 89Zr immunoPET imaging, higher sensitivity of state-of-the art PET/CT systems equipped with silicon photomultiplier (SiPM)-based detector elements may be beneficial as the low positron abundance of 89Zr causes a low signal-to-noise level. Moreover, the long physical half-life limits the amount of activity that can be administered to the patients leading to poor image quality even when using long scan durations. Here, we investigated the difference in semiquantitative performance between the PMT-based Biograph mCT, our clinical reference system, and the SiPM-based Biograph Vision PET/CT in 89Zr immunoPET imaging. Furthermore, the effects of scan duration reduction using the Vision on semiquantitative imaging parameters and its influence on image quality assessment were evaluated. Methods: Data were acquired on day 4 post 37 MBq 89Zr-labelled mAb injection. Five patients underwent a double scan protocol on both systems. Ten patients were scanned only on the Vision. For PET image reconstruction, three protocols were used, i.e. one camera-dependent protocol and European Association of Nuclear Medicine Research Limited (EARL) standards 1 and 2 compliant protocols. Vision data were acquired in listmode and were reprocessed to obtain images at shorter scan durations. Semiquantitative PET image parameters were derived from tumour lesions and healthy tissues to assess differences between systems and scan durations. Differently reconstructed images obtained using the Vision were visually scored regarding image quality by two nuclear medicine physicians. Results: When images were reconstructed using 100% acquisition time on both systems following EARL standard 1 compliant reconstruction protocols, results regarding semiquantification were comparable. For Vision data, reconstructed images that conform to EARL1 standards still resulted in comparable semiquantification at shorter scan durations (75% and 50%) regarding 100% acquisition time. Conclusion: Scan duration of 89Zr immunoPET imaging using the Vision can be decreased up to 50% compared with using the mCT while maintaining image quality using the EARL1 compliant reconstruction protocol. [ABSTRACT FROM AUTHOR]

Globally, COVID-19 affected radiopharmaceutical laboratories. This study sought to determine the economic, service, and research impacts of COVID-19 on radiopharmacy. This online survey was conducted with the participation of employees from nuclear medicine and radiopharmaceutical companies. The socioeconomic status of the individuals was collected. The study was participated by 145 medical professionals from 25 different countries. From this work, it is evident that 2-deoxy-2-[18F]fluoro-D-glucose (2-[18F]FDG), and 99mTc-labeled macro aggregated albumin 99mTc-MAA were necessary radiopharmaceuticals used by 57% (83/145and 34% (49/145;) respondents, respectively for determining how COVID infections affect a patient's body. The normal scheduling procedure for the radiopharmacy laboratory was reduced by more than half (65%; 94/145). In COVID-19, 70% (102/145) of respondents followed the regulations established by the local departments. Throughout the pandemic, there was a 97% (141/145) decrease in all staffing recruitment efforts. The field of nuclear medicine research, as well as the radiopharmaceutical industry, were both adversely affected by COVID-19. [ABSTRACT FROM AUTHOR]

Studying the power quality (PQ) is an essential issue to ensure the safe and accurate operation of sensitive equipment particularly for nuclear installations. Assessment of PQ involves collecting and analysing data resources and then evaluating it with reference to PQ standards. There are many alternatives for PQ and it is difficult to make an appropriate selection among them in the existence of their multiple criteria which are usually conflicted. So this selection subject can be classified as a Multi Criteria Decision Making (MCDM) problem. To do so, a reliable and scientific method for studying and evaluating the overall system PQ is required. This study aims to assess performance of PQ for the electrical power system at a Nuclear Research Reactor (NRR) during a certain period using multiple measures for the most decisive PQ phenomena. It focuses on a number of the most important PQ phenomena namely frequency fluctuation (deviation), unbalances of current and voltage, current and voltage harmonic distortion, flicker and power factor. After combining all results into six samples (alternatives), the criteria weights are determined based on an objective method for weighting which is called CRITIC method. Then, the alternatives are ranked using compromise MCDM method-VIKOR method. The obtained results are analyzed and discussed to evaluate performance of NRR electrical system from the PQ view. It showed that the compromise solution that obtained by CRITIC-VIKOR can be a guide to facilitate the PQ evaluation of nuclear installation electrical system. Also, it can empower the operators with the benefits of benchmarking and monitoring a single index instead of several indices. Moreover, it is very useful for helping stakeholders to understand how the PQ performance changes under a certain operating condition of the facility. Finally, it is can be considered as a good model to weight each PQ phenomena and identify the time intervals for best and worst total PQ in NRR. [ABSTRACT FROM AUTHOR]

Interview of Weizsäcker (by Dieter Hoffmann, June 3, 1992) on Farm Hall and the German uranium project (reprinted from the 1993 edition). Letters (to family and colleagues) from Gerlach, Heisenberg, von Laue, Weizsäcker. Stephan Schwarz received his Ph.D. degree in physics at the University of Stockholm and has been employed in the Swedish Agency for Defence Research and the Royal Institute of Technology in Stockholm, the European Nuclear Energy Agency in Paris, and CERN in Geneva. [Extracted from the article]

A precision current source of the PIT11-260 type with a power of 2.2 MW is designed to supply the superconducting structural magnets of the Booster of the NICA collider plant, which is being created at the Joint Institute for Nuclear Research. The source generates periodic trapezoidal current pulses with an amplitude of up to 10 kA with an accuracy of 0.001–0.01%. For this purpose, the source is made on the basis of a modular multilevel transistor voltage converter in combination with a 6.1-MJ capacitive energy-storage device, which reduces the influence of a powerful pulse-periodic load on the public network and removes the problem of penetration of disturbances from the mains into the power-supply circuits of the superconducting magnets. [ABSTRACT FROM AUTHOR]

The flux weighted average cross sections of the 141Pr(γ,n)140Pr, 160Gd(γ,n)159Gd and 162Er(γ,n)161Er nuclear reactions induced by 10 and 15 MeV energy bremsstrahlung photons are measured with offline gamma spectrometry. The cross sections are reported with detailed uncertainties in the associated parameters. The measured cross sections are compared with the theoretical cross sections calculated using TALYS 1.95 code for eight different gamma strength functions. The average cross sections are also compared with the Geant4 Monte Carlo simulations of the nuclear reactions induced by bremsstrahlung photons. The measured cross sections are important for the nuclear database and nuclear astrophysics research. [ABSTRACT FROM AUTHOR]

Thermal neutron detection is a key subject for nuclear physics research and also in a wide variety of applications from homeland security to nuclear medicine. In this work, it is proposed a novel flexible and conformable composite thermal neutron scintillator based on a fully enriched Lithium Tetraborate preparation ( 6 Li 2 10 B 4 O 7 ) combined with a phosphorescent inorganic scintillator powder (ZnS:Ag), and is then distributed into a polydimethylsiloxane matrix. The proposed scintillator shows a good neutron detection efficiency (max. ∼ 57% with respect to the commercial EJ-420), an average light output of ∼ 9000 ph/neutron-capture, a remarkable insensitivity to γ -rays (Gamma Rejection Ratio <10 - 11 ), and an extraordinary flexibility, so as to reach extremely small curvature radii, down to 1.5 mm, with no signs of cracking or tearing. Its characteristics make it suitable to be employed in scenarios where non-standard geometries are needed, for example, to optimize the detector performance and/or maximize the detection efficiency. Finally, the response of a hybrid detector made of a plastic scintillator, wrapped with the proposed scintillator, coupled to a silicon photomultiplier array is described, and the excellent discrimination between γ -rays, fast and thermal neutrons resulting from data processing is demonstrated. [ABSTRACT FROM AUTHOR]

Goiânia, the Goiás State capital, starred in 1987, where one of the largest radiological accidents in the world happened. A teletherapy machine was subtracted from a derelict radiotherapy clinic and disassembled by scavengers who distributed fragments of the 50 TBq 137CsCl source among relatives and acquaintances, enchanted by the blue shine of the substance. During the 15 days before the accident was acknowledged, contaminated recycling materials were delivered to recycling factories in four cities in the state of São Paulo, Brazil, in the form of recycling paper bales. The contaminated bales were spotted, collected, and stored in fifty 1.6 m3 steel boxes at the interim storage facility of the Nuclear and Energy Research Institute (IPEN). In 2017, a check of the content was performed in a few boxes and the presence of high moisture content was observed even though the bales were dry when conditioned and the packages were kept sealed since then. The main objective of this work was to report the fungi found in the radioactive waste after they evolved for 30 years in isolation inside the waste boxes and their role in the decay of the waste. Examination of the microbiome showed the presence of nematodes and fungal communities. The fungi species isolated were Aspergillus quadricinctus, Fusarium oxysporum, Lecanicillium coprophilumi, Scedosporium boydii, Scytalidium lignicola, Xenoacremonium recifei, and Pleurostoma richardsiae. These microorganisms showed a significant capacity to digest cellulose in our trials, which could be one of the ways they survive in such a harsh environment, reducing the volume of radioactive paper waste. These metabolic abilities give us a future perspective of using these fungi in biotechnology to remediate radioactively contaminated materials, particularly cellulose-based waste. [ABSTRACT FROM AUTHOR]

In this paper, the results of lidar monitoring of magmatic aerosol variation are presented. The lidar was installed in a hot dead-end tunnel at the end of the auxiliary adit of the Baksan Neutrino Observatory (BNO) of the Institute for Nuclear Research, Russian Academy of Sciences, which is located above the small magma chamber of the Elbrus Volcanic Center. A sharp (within ~30 min) threefold increase in the aerosol concentration in the hot tunnel was detected (October 28, 2019, 22:30 UTC). The analysis involved data on volumetric radon activity, air temperature, and humidity. A synchronous increase in temperature, humidity, and aerosol concentration in the tunnel, as well as their correlation with the deformation of the Earth's crust by tidal waves, which is monitored at the BNO with a laser strainmeter, was revealed. However, the threefold jump did not appear in these signals. The totality of data confirms the existence of a hot magma chamber at the base of Mount Andyrchi that was previously discovered by a small-aperture seismometer group. The assumption that the release of gases from the magma chamber could provide a jump in the concentration of aerosols without disturbing other parameters is discussed. [ABSTRACT FROM AUTHOR]

Sol–gel vitrification can be used to rapidly produce solid, vitreous materials to support nuclear forensics research. This work investigates three sol–gel synthetic approaches' ability to retain fission products within the glass as a function of drying temperature. Eight of the ten fission products studied were quantitatively retained (less than 5% losses) at temperatures up to 600 °C for glasses prepared using an acidic catalyst and at temperatures up to 300 °C for glasses prepared using a basic catalyst. Both systems show partial loss of ruthenium and complete loss of iodine at temperatures above 300 and 100 °C, respectively. [ABSTRACT FROM AUTHOR]

National Nuclear Sciences and Technologies Conference (NBTK) was held by Ege University (1980), Turkish Atomic Energy Authority (ÇNAEM) (1984), Istanbul Technical University (1989), Atatürk University (1990), Ege University (1991), Uludag University (1993), Istanbul Technical University (1996), Erciyes University (2003), Ege University (2005), Mugla University (2009) and Ege University (2016). The "International Nuclear Sciences and Technologies Conference (INSTEC-2022)" congress was held by the Ege University Institute of Nuclear Sciences in association with the Turkish Energy, Nuclear and Mineral Research Agency (TENMAK) on 19-22 October 2022 in Pine Bay Resort Hotel Kusadasi/Aydin. INSTEC-2022, which aims to bring together the world's leading scientists who continue their research in the nuclear field, was held at the international level for the first time in 2022. [Extracted from the article]

The primary factors in the radiation exposure received by the human population from soil and water are natural radioactivity, uranium isotopes, and thorium isotopes. High levels of nuclear radiation exposure are now one of the leading causes of cancer. Radon and its offspring in the biosphere have long been the topic of research. Various experts from all over the world have undertaken several investigations on the quantity of radon in surface and groundwater supplies. An attempt was made to measure the levels of radon in groundwater in and around Areekode using a smart radon monitor (SRM) developed by the Baba Atomic Research Centre (BARC) in Mumbai. Groundwater/Bore well water in this region had 222Rn in concentrations ranging from 0.37±0.03Bq/L to 3.53±0.10Bq/L. The environmental protection agency's allowable limit of 11.1 kBq/m3 was met by all of the samples. [ABSTRACT FROM AUTHOR]

The np scattering length was obtained in a kinematically complete experiment devoted to studying the nd-breakup reaction at low energies of neutrons from the RADEX channel of Institute for Nuclear Research, Russian Academy of Sciences. In this experiment, two neutrons were detected on different sides of the primary-beam axis. The scattering-length values of 1.1 fm and fm obtained at and 11 MeV, respectively, from a comparison of the experimental dependence of the nd-breakup reaction yield on the relative energy of the np pair with the results of a simulation differ significantly from the corresponding values found in an experiment that studied free np scattering. This is indicative of an efficient enhancement of np interaction in the presence of a third nucleon. [ABSTRACT FROM AUTHOR]

Fault diagnosis of Medium Voltage power Cables (MVCs) research nuclear reactor, incredibly inaccessible/remote ones, has to be carefully identified, located, and fixed within a short time. Therefore, this paper proposes a perfect simultaneous fault diagnosis scheme based on Multiclass Support-Vector Machine (MCSVM) in the fractional Fourier domain. First, the three-phase sending currents are simulated under different conditions then their features are extracted using Discrete Fractional Fourier Transform (DFRFT). Afterward, the features reduction process occurs via the Singular Value Decomposition (SVD) approach. MCSVM scheme is used to diagnose faults (i.e., discover, categorize, and trace) using reduced features outcome from DFRFT and SVD stages. Alternating Transient Program/Electromagnetic Transient Program (ATP/EMTP) simulations have been carried out for 22 kV unreachable MVC. Different kernels of SVM, i.e., linear, quadratic, or polynomial, and diverse factors of DFRFT, i.e., α, are investigated in simulations to obtain the optimum performance (i.e., best α and kernel pair). Hence, performance analysis of the proposed diagnosis method under different conditions (i.e., various fault resistances, locations, and inception angles) concluded two highest accuracy and lowest time settings, which were found at α = 0.5 (for both) quadratic kernel, and linear kernel, respectively. Moreover, the linear kernel achieves 99.8% accuracy rate, the lowest execution time (10 ms), and fault tracing error rate of 0.525789%, which is proper for real-time applications. Besides, our proposed method is more reliable and accurate against variable operating conditions (fault resistances, distances, and inception angles), leading to more reliable power production systems. [ABSTRACT FROM AUTHOR]