Field Of Nuclear Physics Research Articles

Study of Cluster Decays Including Those Leading to Doubly Magic Nucleus 298114 and Branching Ratios Relative to Alpha Decay

The study of superheavy nuclei (SHN) and their decay properties is one of the rapidly growing fields in nuclear physics. Using the CYE model, we have already studied the decay properties of the alpha decay, cluster decay, and spontaneous fission of the heavy and superheavy nuclei. In the present work, we will examine the effects by incorporating hexacontatetrapole (β6) parameter in the parent nucleus along with the quadrupole (β2), and hexadecapole (β4) deformations of the decaying parent nucleus emitting clusters 84Be and 126C. These deformations lower the half-life values, because they reduce the height and width of the potential barrier. Additionally, the creation of the doubly magic daughter 298114 from different decaying nuclei is computed. The calculated half-lives are compared with other models and are found to be in a good agreement. The branching ratios relative to the alpha-decay have also been calculated.

Research on the Detection Principle of Coal Ash by X-Ray Transmission Based on FLUKA

This study addresses the timely and accurate measurement of coal ash content by proposing a detection model based on nuclear science technology, which is validated using FLUKA 4-4.0 simulation software. The background provided highlights the fact that coal ash content is a critical sales indicator, and its precise measurement is essential for adjusting production parameters in coal preparation plants. In terms of methodology, this study employs the widely used FLUKA4-4.0 software in the field of nuclear physics to simulate X-ray transmission through coal, investigating the impact of changes in coal type on the accuracy of ash measurements. The results indicate that, when the proportions of high-atomic-number elements in coal remain constant, the ash measurement results are accurate and reliable. However, significant fluctuations occur when these proportions change. The conclusion emphasizes the fact that variations in coal type are the primary cause of inaccuracies in ash measurement, particularly when the ratios of high-atomic-number elements are altered. This research provides a new perspective on the online measurement of coal ash content and offers theoretical support for improving measurement accuracy.

Использование цифровых технологий в практике преподавания русского языка как иностранного на подготовительном факультете в российском вузе

The article examines the specificities of teaching Russian as a foreign language to pre-graduate and pre-doctoral students in the field of nuclear physics and technologies using digital tools and methods. The work considers the benefits of teaching language for specific purposes with the application of digital tools. The research aims to determine how using digital tools can enhance the effectiveness of teaching Russian as a foreign language for specific purposes in groups of pre-graduate and pre-doctoral students. The research is novel in that it is the first one to formulate the differences between the educational process for students in graduate programs and programs for training scientific and pedagogical personnel in postgraduate studies, compared to undergraduate and specialist programs. In addition, an experiment is conducted to confirm the effectiveness of using digital tools when teaching these student cohorts. The article provides a detailed description of the system of tools used in classes at the National Research Nuclear University “MEPhI” in groups of pre-graduate and pre-doctoral students. As a result of the research, it has been revealed that in the case of a systemic and methodologically justified use of digital tools in Russian as a foreign language classes, the effectiveness of the learning process increases, interest in learning Russian and nuclear physics is stimulated through practical assignments and research activities, and student motivation is also enhanced.

A coherent microscopic picture for the exotic structure of 11Be

The neutron-rich nucleus 11Be is one of the most enigmatic exotic nuclei in the periodic table. It exhibits a multitude of unique and intriguing phenomena within a single nucleus, including the halo phenomenon, clustering structure, and parity inversion. A unified description of these exotic properties represents a significant challenge for the nuclear physics field. By employing the axially deformed relativistic Hartree-Fock-Bogoliubov (D-RHFB) model, we have successfully reproduced the parity inversion and the one-neutron halo in 11Be, and revealed the underlying cluster structure. It is found that the intrusion of the sd-shell, which results in the parity inversion, is coherently connected with the halo and cluster structures. In particular, the s-wave is responsible for the halo formation, and the mixing of 2s1/2- and 1d5/2-waves enhances the cluster structure. This work elucidates the coherence between the parity inversion and the halo/cluster structures of 11Be, and addresses the long-standing challenge of providing a unified explanation for the multiple exotic phenomena observed in 11Be.

PROBING THE NUCLEAR STRUCTURE OF EXOTIC 33Mg ISOTOPE

Research on the nuclear structure of exotic isotopes, such as 33Mg, is an exciting and cuttingedge field of nuclear physics. Exotic isotopes are typically those that are far from the stable region of the nuclear chart and often exhibit unique properties that can help us better understand the fundamental forces and structure of atomic nuclei. In this paper the largescale shell model calculations are performed within the model spaces SDPFMU, to study the positive- and negative-parity energy levels and electromagnetic transitions in the exotic 33Mg isotope. Core-polarization effects on reduced transition probability are introduced through first order perturbation theory, which allows for higher energy configurations through excitations of nucleons from core orbits to that outside model space up to . The corepolarization effects have been improved the agreement of B(E2) with their corresponding experimental data, and have ignorable effect on B(M1)

Exploration of the ground state properties of neutron-rich sodium isotopes using the deformed relativistic mean field theory in complex momentumrepresentations with BCS pairings* *Partly supported by the National Natural Science Foundation of China (11935001, 11575001), the Natural Science Foundation of Anhui Province (2008085MA26), Anhui project (Z010118169), the Heavy Ion Research Facility in Lanzhou (HIRFL) (HIR2021PY007), and the project of Key

This study explores the ground-state characteristics of neutron-rich sodium isotopes, encompassing two-neutron separation energies, root-mean-square radii, quadrupole moments of proton and neutron distributions, single-particle levels of bound and resonant states, and neutron density distributions and shapes. Simultaneously, special attention is paid to the distinctive physical phenomena associated with these isotopes. The deformed relativistic mean field theory in complex momentum representations with BCS pairings (DRMF-CMR-BCS) employed in our research provides resonant states with real physics, offering insights into deformed halo nuclei. Four effective interactions (NL3, NL3*, PK1, and NLSH) were considered to assess the influence of continuum and deformation effects on halo structures. Calculations for odd-even nuclei 35–43Na revealed the dependence on the chosen effective interaction and number of considered resonant states. Neutron occupation patterns near the Fermi surface, particularly in orbitals and , were determined to be crucial in halo formation. The study provided detailed insights into the density distributions, shape evolution, and structure of neutron-rich sodium isotopes, contributing valuably to the field of nuclear physics.

Investigation of (n,x) reactions on enriched Ge targets at 15.7 MeV at the upgraded facility of NCSR “Demokritos”

Neutron induced reaction cross-section measurements display special interest both for fundamental research in the Nuclear Physics field and many practical applications. The Institute of Nuclear and Particle Physics (INP) of the National Centre for Scientific Research Demokritos (N.C.S.R. “D”) hosts the 5.5 MV T11/25 Van de Graaff accelerator, which is the only accelerator used in Greece for research purposes. This accelerator recently underwent a major upgrade, including the installation of a new pelletron charging system, two new ion sources, a new gas stripper and beam optics. This neutron facility can produce quasi-monoenrgetic neutron beams in the energy range ∼16-19 MeV via the 3 H(d,n)4 He (D-T) reaction, employing a tritiated Titanium target (TiT). The neutron induced cross sections of a total of nine reaction channels have been experimentally measured in the present work, via the activation technique, using enriched Ge targets. These targets produce more accurate cross-section results, in comparison with the - most commonly used in bibliography - nat Ge samples, since they do not suffer from contaminating reactions that produce the same residual nucleus. Monte Carlo simulations were also performed via the combined use of MCNP5 and NeuSDesc codes for the simulation of the neutron beam.

NUCLEAR STRUCTURE STUDY OF THE HALO NUCLEI

The existence of halo nuclei is one of the major important discoveries in the field of nuclear physics. These nuclei are treated as loosely bound system in which a core of normal nuclear density is surrounded by so-called neutron (or proton) halo of diluted nuclear matter. Many theoretical investigations have attempted to understand these nuclei, which exist at light to heavy masses. The phenomenon of nuclear halo is a quantum effect that occurs in nuclei due to the presence of valence nucleons with low separation energy and I = 0, 1 (low angular momentum), and is manifested by the extraordinarily large radii of these nuclei. The core plus halo model is commonly used to describe halo nuclei. This model recognizes the need to treat the core and the halo neutrons or protons separately. By considering different model spaces for the core and the halo nucleons, we can better explain the properties of halo nuclei. This separation is justified by the fact that the valence nucleons in a halo nucleus have different properties compared to the core. Halo nuclei at rest cannot be used as target due to their short-lived species and extraordinary ratio of neutrons and protons (either neutron-rich or proton-rich). Instead, they can be studied through direct reactions with a radioactive isotope beam, employing inverse kinematics where the role of the beam and target are exchanged. In order to investigate the charge and matter densities of these nuclei, total and differential reaction cross section analyses of proton scattering on halo nuclei have been carried out using various theoretical and phenomenological methods

Multiplicity counting using organic scintillators to distinguish neutron sources: An advanced teaching laboratory

In this advanced instructional laboratory, students explore complex detection systems and nondestructive assay techniques used in the field of nuclear physics. After setting up and calibrating a neutron detection system, students carry out timing and energy deposition analyses of radiation signals. Through the timing of prompt fission neutron signals, multiplicity counting is used to carry out a special nuclear material (SNM) nondestructive assay. Our experimental setup is comprised of eight trans-stilbene organic scintillation detectors in a well-counter configuration, and measurements are taken on a spontaneous fission source as well as two (α,n) sources. By comparing each source's measured multiplicity distribution, the resulting measurements of the (α,n) sources can be distinguished from that of the spontaneous fission source. Such comparisons prevent the spoofing, i.e., intentional imitation, of a fission source by an (α,n) neutron source. This instructional laboratory is designed for nuclear engineering and physics students interested in organic scintillators, neutron sources, and nonproliferation radiation measurement techniques.

Everyday life of women in Dubna of the 1950s-1960s

The article analyzes the structures of women's everyday life in the “science city” of Dubna, designed to become a showcase of socialism in the USSR of the 1950s-60s. We believe that during the years of the “Khrushchev thaw” and the rise of scientific centers throughout the country, women in these new towns found themselves in non-trivial conditions for traditional Soviet women's everyday life, where they gained the opportunity to implement their own life strategies in science and related fields. Few took advantage of this opportunity, however. Residents of the closed town of Dubna had access to special supplies and social infrastructure that was exemplary for that time; they were able to contact foreigners and enjoyed many cultural privileges. Triangulation of the sequences of biographical stories conveyed by representatives of different social strata, comparing them with media materials and extracts from normative sources led us to the conclusion that the traditional gender contract, subjected to only slight erosion in the first decades of the Soviet power, did not disappear at all - in fact, it took root in the “city of the future” inhabited by designers, inventors, and scientists. Due to the rigidity of this contract, the majority of Dubna's residents did not succeed in becoming, and did not want to become, independent actors seeking to declare themselves and their professional ambitions in science or the public sphere. We attempt to reveal the social role of such women through the prism of everyday life and social memory. We argue that it boiled down to the fulfillment of social expectations, the readiness to remain in service roles and provide a reliable rear support for their husbands-scientists who worked on major Soviet projects in the field of nuclear physics.

Clustering states in neutron-rich nuclei

The study of clustering states in neutron-rich nuclei is an important subject of research in the field of nuclear physics, steadily growing in interest in the international scientific community. In this context, break-up reactions play an important role for the characterization of exotic states in radioactive light nuclei, like neutron halos around stable cores, α-clustering structures or exotic clusters. The CLIR (Clusters in Light Ion Reactions) experiment was performed at INFN - Laboratori Nazionali del Sud (LNS), aiming at the investigation of such states in light radioactive nuclei, by producing a radioactive beam at the FRIBs facility. Reaction products were detected by the CHIMERA multidetector, coupled with four telescopes of the FARCOS array. Calibrations of the tagging system and of the FARCOS telescopes have been performed, for which accurate procedures have been carried out. In this paper, results on the analysis will be presented. Moreover, a brief review on the new fragment separator FRAISE, currently under construction at LNS, will be given.

Research on the performance of a diamond detector for the cross-section measurements at CSNS Back-n

The measurement of cross-section holds great significance in the field of nuclear physics. The Back-n white neutron facility located within the China Spallation Neutron Source (CSNS) has emerged as a significant contributor to this effort, offering high brightness and stable neutrons with a wide energy range (10°–108 eV). In the harsh environment of Back-n, diamond detectors have emerged as a promising option due to their high radiation hardness and compact size. A bi-parameter experiment (neutron time of flight and deposited energy) utilizing a single-crystal diamond was carried out at Back-n. The obtained time structure of the proton beam at CSNS aligns with previously reported results, thereby validating the approach. Additionally, the bi-parametric contour plot facilitated the identification of event bands corresponding to 12C(n,α0)9Be, 12C(n,n’)3α and 6Li(n,α)3H reactions. A simulation study using MATLAB analyzed the energy deposition distribution of 3–11 MeV neutrons in diamond detectors, which agreed with the identified event bands for the 12C(n,α0)9Be and 12C(n,n’)3α reactions. The peak positions of reaction channels within distinct neutron energy ranges demonstrated a remarkable concordance, with most below 2. This is the first time a diamond detector has been tested at Back-n. The results of the experiment have significant implications for the development of nuclear data measurement using diamond detectors at Back-n.

The effect of fission products Xe and Cs on the thermal conductivity of the U3Si2 lattice: a first-principles study

In the past decades, uranium silicide (U3Si2) as a promising accident tolerant fuel (ATF) has drawn considerable attention in the field of nuclear physics. In comparison with traditional nuclear fuel (UO2), the U3Si2 has higher thermal conductivity and uranium density, thereby resulting in lower centerline temperatures and better fuel economy. However, during the nuclear fission reaction, some unexpected fission products, such as Xe and Cs, are released and form the defective states. In this study, we explore the influence of Xe and Cs on the thermal conductivity of the U3Si2 lattice from 200 to 1500 K using density functional theory calculations combined with Boltzmann transport equation. Our results reveal that the lattice and electronic thermal conductivities of defective U3Si2 are reduced at a constant temperature, as compared with that of ideal system, thus resulting in a decrease of the total thermal conductivity. In the case of Cs occupation at U1 site, the total thermal conductivity (4.42 W mK−1) is decreased by ∼56% at 300 K, as compared with the value of 9.99 W mK−1 for ideal system. With U1 and Si sites being occupied by Xe, the total thermal conductivities (4.45 and 6.52 W mK−1) are decreased by ∼55% and 35% at 300 K, respectively. The presented results suggest that the U3Si2 has potential as a promising ATF at high temperatures.

Application of machine learning methods for filling and updating nuclear knowledge bases

The paper deals with issues of designing and creating knowledge bases in the field of nuclear science and technology. The authors present the results of searching for and testing optimal classification and semantic annotation algorithms applied to the textual network content for the convenience of computer-aided filling and updating of scalable semantic repositories (knowledge bases) in the field of nuclear physics and nuclear power engineering and, in the future, for other subject areas, both in Russian and English. The proposed algorithms will provide a methodological and technological basis for creating problem-oriented knowledge bases as artificial intelligence systems, as well as prerequisites for the development of semantic technologies for acquiring new knowledge on the Internet without direct human participation. Testing of the studied machine learning algorithms is carried out by the cross-validation method using corpora of specialized texts. The novelty of the presented study lies in the application of the Pareto optimality principle for multi-criteria evaluation and ranking of the studied algorithms in the absence of a priori information about the comparative significance of the criteria. The project is implemented in accordance with the Semantic Web standards (RDF, OWL, SPARQL, etc.). There are no technological restrictions for integrating the created knowledge bases with third-party data repositories as well as metasearch, library, reference or information and question-answer systems. The proposed software solutions are based on cloud computing using DBaaS and PaaS service models to ensure the scalability of data warehouses and network services. The created software is in the public domain and can be freely replicated.

ASPECT-BET: An sdd-SPECTrometer for BETa decay studies

We present the status of the ASPECT-BET (An sdd-SPECTrometer for BETa decay studies) project which is aimed at developing a new detection strategy to perform high-precision, high-accuracy measurements of the energy spectra of beta decays of interest for the physics community, in particular in the field of nuclear physics, double beta decay and reactor neutrinos. The aim is to exploit a relatively novel spectroscopic technique based on Silicon Drift Detectors. An SDD-spectrometer, equipped with all the ancillary detectors required to reject events with only a partial energy deposition in the main sensitive elements, will provide high-statistics and virtually zero-background data. In order to isolate and study the systematic uncertainties, the statistical error on the measured spectra has to be reduced to a negligible level, balancing source activity, measurement duration and background. Reliable and well understood Montecarlo simulations are a key component of this application, as they provide a model for the response functions of the spectrometer, to be deconvolved from the data in order to correctly reconstruct the original spectral shapes. Thanks to the flexibility of the SDD detector technology, the here presented spectrometer could be coupled to a variety of beta sources, ranging from nuclei deposited on the surface of SDDs to minimise source self-absorpion to short-lived isotopes created and collected at unstable isotope beams like ISOLDE at CERN or the exotic beams at LNS, Catania. The current status of the technology, as well as some preliminary sensitivity studies, are presented and discussed.

A brief history of Florentine physics from the 1920s to the end of the 1960s

The history of the Institute of Physics at the University of Florence is traced from the beginning of the 20th century, with the arrival of Antonio Garbasso as Director (1913), to the 1960s. Thanks to Garbasso's expertise, not only did the Institute gain new premises on Arcetri hill, where the Astronomical Observatory was already located, but it also formed a brilliant group of young physicists made up of Enrico Fermi, Franco Rasetti, Enrico Persico, Bruno Rossi, Gilberto Bernardini, Daria Bocciarelli, Lorenzo Emo Capodilista, Giuseppe Occhialini and Giulio Racah, who were engaged in the emerging fields of Quantum Mechanics and Cosmic Rays. This Arcetri School disintegrated in the late 1930s for the transfer of its protagonists to chairs in other universities, for the environment created by the fascist regime and, to some extent, for the racial laws. After the war, the legacy was taken up by some students of this school who formed research groups in the field of nuclear physics and elementary particle physics. As far as theoretical physics was concerned, after the Fermi and Persico periods these studies enjoyed a new expansion towards the end of the 1950s, with the arrival of Giacomo Morpurgo and above all, that of Raoul Gatto, who created the first real Italian school of Theoretical Physics at Arcetri.

Study of the 176Hf(n,2n)175Hf cross section at 18.9 MeV

Neutron nuclear reactions can provide significant information in the field of nuclear physics and applications. Hafnium (Hf) is one of the rare-earth isotopes with a relative large neutron total cross-section in the thermal neutron energy region and neutron induced reactions in reactor materials could lead to the production of long-lived isomeric states of Hf isotopes. Thus, the knowledge of neutron cross-sections on Hf isotopes is of great importance for basic research in Nuclear Physics as well as for applications concerning the interaction of neutrons with matter. In this study measurements of experimental cross section for the 176Hf(n,2n)175Hf and 180Hf(n,n΄γ)180mHf reactions were carried out, using the activation technique. The neutron beam energy at 18.9 MeV was produced via the 3H(d,n)4He reaction at the 5.5 MeV Tandem Van de Graaf accelerator laboratory of NCSR “Demokritos”. A thin metallic foil of natural Hf was used, while for the determination of the neutron flux at the target position a reference foil of Al was placed at the back of the Hf target. The irradiation was continuous for 28 hours leading to a total neutron fluence of 1010 n/cm2 and a BF3 detector was used for monitoring the neutron flux during the irradiation. After the end of irradiation, the activity of the Hf target and the Al foil were measured off-line by two HPGe detectors. Both detector efficiencies were obtained using a calibrated 152Eu source, placed in the same distance as the target and the reference foil. The 176Hf(n,2n)175Hf reaction has been corrected from the contribution of 177Hf(n,3n)175Hf and the 174Hf(n,γ)175Hf reactions and the 180Hf(n,n΄γ)180mHf reaction from the 179Hf(n,γ)180mHf. Theoretical calculations of the 174Hf(n,2n)175Hf, 176Hf(n,2n)175Hf and 180Hf(n,n΄γ)180mHf reaction cross-sections have also been performed using the nuclear statistical code “EMPIRE 3.2.3” and they have been compared with the data.

Improvement of evaporation residual cross sections for superheavy nuclei using a neural network method

Synthesizing heavier superheavy nuclei (Z>118) in the laboratory and probing the charge limit of atomic nuclei are difficult problems in the field of nuclear physics. Theoretically accurate calculations of the evaporation residual cross section (ERCS) play the key roles for synthesis of new superheavy nuclei. In this work, based on the neural network method, the evaporation residual cross sections of superheavy nuclei calculated by the dinuclear system model are improveded to make the theoretical results closer to the experimental values, which substantially increased the accuracy of the theoretical description. In particular, the results for the evaporation of 5 neutrons are greatly improved.

Lithium photodisintegration with unpolarized photon beams at near threshold energies

The study of photonuclear reactions with lithium targets i.e. photodisintegration of lithium in addition to other photonuclear reactions is of considerable interest to the fields of nuclear physics, astrophysics, laser physics and several applications such as non - destructive testing of nuclear materials. We propose to study photodisintegration of lithium with unpolarized photon beams at near threshold energies. Our model independent theoretical approach, which makes use of irreducible tensor techniques, is well suited for making predictions on the spin observables as well as the differential cross section. In this paper we analyze the reaction channel 7Li + γ → 6Li + n by using unpolarized photons.

Vienna Group within the framework of the German nuclear project

The work deals with the large-scale research in the field of nuclear physics and chemistry, which was carried out in the framework of the German Nuclear Project ("Uranverein") from 1939 to 1945 in Austria, which is completely unknown in the Russian literature. The University of Vienna, the Radium Institute of Vienna, the Neutron Institute, as well as the Vienna Higher Technical School took part in the work. Within the framework of the project, the following topics were developed: the creation of a nuclear reactor, the creation of powerful accelerator technology, the creation and study of transuranic elements, the development of computer technology, as well as conducting biomedical radiation experiments