Experimental Determination of Excitation Function Curves through the Measurement of Thick Target Yields in Liquid Targets: The Examples of the 68Zn(p,n)68Ga and 64Zn(p,α)61Cu Nuclear Reactions

The present work describes a method to determine excitation function curves and, therefore, cross-sections, making use of the irradiation of liquid targets at distinct energies in a biomedical cyclotron. The method relies on the derivative of experimentally measured thick target yield curves to determine the corresponding excitation function curves. The technique is presented as a valid and practical alternative to the commonly used activation method combined with the stack monitor technique, whose implementation in liquid targets offers practical difficulties. The working principle is exemplified by presenting the results obtained for the clinically relevant 68Zn(p,n)68Ga and the 64Zn(p,α)61Cu nuclear reactions, obtained though the irradiation of liquid targets containing dissolved natural zinc.

The Creation Process of The First Particle from the Absolute Void

In this study, we discuss the properties of absolute vacuum space and how these properties can play a vital role in creating a mechanism in which the very first particle gets created simultaneously everywhere and we find the limit in which when the absolute vacuum volume reaches will lead to the collapse that leads to the creation of the first particle. This discussion is made following to the elementary dimensions theory study that was peer-reviewed at the end of 2020, everything in the universe is made from four elementary dimensions, these dimensions are the three spatial dimensions (X, Y, and Z) and the Vacuum resistant as the factor of change among the four, time itself wasn’t considered as the fourth dimension, rather time corresponds to a factor of change, and during the research it was found out that the Vacuum resistant is the factor of change in the Absolute Vacuum space, where time is a hypothetical concept, that represents changes during certain events compared to a constant change rate event.Therefore, time does exist, but as a factor of change, and as the Vacuum resistant in the absolute vacuum space, Time= factor of change= Vacuum resistant. In the study, the internal and external vacuum resistant volume equivalent is found, External Vacuum resistant=3.2857602*10^15 *mass. This equation is used to identify the amount of Free external vacuum resistant created during nuclear fission and fusion: Initial mass of the excited nucleuses mass of the created new nucleuses+ 3.2857602*10^15 * the lost Mass. In elementary dimensions, the energy created during nuclear reactions is equivalent to the free External vacuum resistant created through nuclear reactions, and mass is equivalent to the internal Vacuum resistant.

Joint transmutation of stable Cs and Sr isotopes in microbiological systems and prospects for accelerated deactivation of liquid radioactive waste

It was found during the research that in the experimental and control bioreactors, which at the beginning of the experiments contained only cesium and strontium, by the end of the experiments, yttrium and barium were found. These isotopes are formed as a result of low-energy nuclear reactions involving protons. In addition, in experimental bioreactors with an optimal composition, a two to threefold increase in the concentration of yttrium was recorded in comparison with the control non-optimal experiments. Accumulation of strontium and cesium in biomass was registered, which is explained by the process of biosorption. It is known that biosorption is the first step towards nuclear transformation (biotransmutation). At the same time, one of the main conditions for the nuclear transformation of biomass elements is its maximum efficient growth. An unexpected fact discovered during the experiment is that yttrium and barium were also found in the control bioreactor, where no biomass was added before the experiment, but only deionized water, glucose, and the initial stable cesium and strontium salts. It is important to note that these elements were not detected in the analysis of the initial salts, substrates, and deionized water. Most likely, the presence of yttrium and barium is due to inoculation of the control fluid of the bioreactor (where no biomass pellets were added) with microorganisms from the experimental bioreactors during their periodic opening for taking current pH samples and adding glucose. Also, the work recorded a decrease in the content of cesium and strontium in the liquid by 20% and 55%, respectively, which goes beyond the statistical error.

Combining Halo-EFT Descriptions of Nuclei and Precise Models of Nuclear Reactions

The clear separation of scales observed in halo nuclei between the extended halo and the compact core makes these exotic nuclei a perfect subject for effective field theory (EFT). Such description leads to a systematic expansion of the core-halo Hamiltonian, which naturally orders the nuclear-structure observables. In this short review, I show the advantages there are to include Halo-EFT descriptions within precise models of reactions. It helps identifying the nuclear-structure observables that matter in the description of the reactions, and enables us to easily bridge predictions of nuclear-structure calculations to reaction observables. I illustrate this on breakup, transfer and knockout reactions with $$^{11}$$ 11 Be, the archetypical one-neutron halo nucleus.

B.U. RODIONOV’S HYPOTHESIS OF THREADED MATTER AND SOME OF ITS APPLICATIONS

The article contains a brief biography and main directions of scientific activity of the doctor of physical and mathematical sciences, professor, academician of the Russian Academy of Natural Sciences, member of the Russian Philosophical Society Boris Ustinovich Rodionov. A brief overview of ideas related to the threaded matter hypothesis and some of its applications to the analysis of the phenomenology of low energy nuclear reactions, the results of measurements with a fammeter, and the problem of nonlocality is given.

Collisions of Nucleons with Atoms: Calculated Cross Sections and Monte Carlo Simulation

After a summary description of the theory of elastic collisions of nucleons with atoms, we present the calculation of a generic database of differential and integrated cross sections for the simulation of multiple elastic collisions of protons and neutrons with kinetic energies larger than 100 keV. The relativistic plane-wave Born approximation, with binding and Coulomb-deflection corrections, has been used to calculate a database of proton-impact ionization of K-shell and L-, M-, and N-subshells of neutral atoms These databases cover the whole energy range of interest for all the elements in the periodic system, from hydrogen to einsteinium (Z = 1–99); they are provided as part of the penh distribution package. The Monte Carlo code system penh for the simulation of coupled electron-photon-proton transport is extended to account for the effect of the transport of neutrons (released in proton-induced nuclear reactions) in calculations of dose distributions from proton beams. A simplified description of neutron transport, in which neutron-induced nuclear reactions are described as a fractionally absorbing process, is shown to give simulated depth-dose distributions in good agreement with those generated by the Geant4 code. The proton-impact ionization database, combined with the description of atomic relaxation data and electron transport in penelope, allows the simulation of proton-induced x-ray emission spectra from targets with complex geometries.

Activities in Divertor Reflector and Linear Plates Using WCLL and HCPB Breeding Blanket Concepts

In fusion devices, such as European Demonstration Fusion Power Reactor (EU DEMO), primary neutrons can cause material activation due to the interaction between the source particles and the targeting material. Subsequently, the reactor’s inner components become activated. For safety and safe performance purposes, it is necessary to evaluate neutron-induced activities. Activities results from divertor reflector and liner plates are presented in this work. The purpose of liner shielding plates is to protect the vacuum vessel and magnet coils from neutrons. As for reflector plates, the function is to shield the cooling components under plasma-facing components from alpha particles, thermal effects, and impurities. Plates are made of Eurofer with a 3 mm layer of tungsten, while the water is used for cooling purposes. The calculations were performed using two EU DEMO MCNP (Monte Carlo N-Particles) models with different breeding blanket configurations: helium-cooled pebble bed (HCPB) and water-cooled lithium lead (WCLL). The TENDL–2017 nuclear data library has been used for activation reactions cross-sections and nuclear reactions. Activation calculations were performed using the FISPACT-II code at the end of irradiation for cooling times of 0 s–1000 years. Radionuclide analysis of divertor liner and reflector plates is also presented in this paper. The main radionuclides, with at least 1% contribution to the total value of activation characteristics, were identified for the previously mentioned cooling times.

PRODUCT YIELDS FOR THE PHOTOFISSION OF 239Pu WITH BREMSTRAHLUNG AT 17.5 MeV BOUNDARY ENERGY

The values of relative cumulative yields of 12 products (85mKr, 91mY, 92Sr, 97Zr, 99Mo, 105Ru, 133I, 134I, 135I, 138Cs, 139Ba, 142La, 143Ce) of the 239Pu photofission was measured at a maximum bremsstrahlung energy of 17.5 MeV (av-erage excitation energy ~ 12.03 MeV). 239Pu photofission reaction was stimulated on the electron accelerator of the Institute of Electron Physics NAS of Ukraine – M-30 microtron to simulate the spectra of bremsstrahlung’s photons, secondary electrons, and photoneutrons that hit the 239Pu target, the GEANT4 code was used. The input of accom-panying nuclear reactions to the yield of 239Pu photofission products for the given experimental parameters was also evaluating. The obtained experimental data of the yields of products 239Pu photofission were compared with the program codes GEF and Talys1.9.5 simulations.