Evaluation of calculation methods for excitation functions for production of radioisotopes of iodine, thallium and other elements

The effects of nuclear level density model and alpha optical model potential to the excitation functions of novel therapeutic radionuclides

In this study, the theoretical cross sections of 209Bi(α,2n)211At, 65Cu(α,n)68Ga, 100Ru(α,n)103Pd, and 121Sb(α,n)124I are calculated using TALYS 1.96, incorporating the effects of the alpha optical model potential and nuclear level density models. The validation process involves comparing the calculated cross sections with experimental data and utilizing statistical deviation factors. This comparison allows us to determine the optimal combination of nuclear model parameters for each reaction. The result shows that theoretical calculations which utilized semi microscopic level density models and alpha OMP managed to describe the excitation functions close to the experimental data. The comparison of nuclear model calculations with experimental data plays a crucial role in ensuring the reliability of the data, making it an essential aspect of modern evaluation procedures.

Determination of excitation function for alpha induced reactions on 237Np and 238Pu

The excitation function of the alpha particle-induced reactions on 237Np and 238Pu has been determined for the incident alpha energies ranging from threshold to 50 MeV using TALYS1.95 nuclear reaction code. In this study, the excitation function of (α,xn) reactions on 237Np and 238Pu has been determined by invoking the Jeukenne-Lejeune-Mahaux-Bruyeres Optical model potential. The microscopic nuclear level density from Hilaire's combinatorial table is used to calculate the nuclear level density. Also, the excitation function has been evaluated by using the alpha potential of Watanabe folding approach with Koning-Delaroche spherical optical model potential and McFadden-Satchler potential. Furthermore, all the calculated cross-sections have been compared with the experimental results taken from EXFOR and the available evaluated cross-sections from TENDL2019 nuclear data library. The calculated cross sections using Jeukenne-Lejeune-Mahaux-Bruyeres Optical model potential together with microscopic nuclear level density from Hilaire's combinatorial table incorporating the Skyrme-Hartree-Fock-Bogoliubov calculation results in good correspondence with the experimental values from EXFOR.

A study on the cross-section data of 43,44m,46,47Sc isotopes via (d,x) reactions on natural abundance targets under the effects of deuteron optical models

Many studies have investigated the influence of theoretical models and factors involved in the acquisition of cross-section data of a nuclear reaction. The implications of different models of various variables such as level density, gamma strength function, and optical potentials on cross-section calculations whether used solo or jointly are investigated in a significant portion of the works conducted in this perspective. The aim of this particular study is to investigate the influence of different optical models on the cross-section calculations in production of several scandium isotopes, known for various medical uses, from several targets with natural abundances by (d,x) reactions. For this purpose, the cross-section calculations using five available deuteron optical models of TALYS code in ^natTi(d,x)⁴³Sc, ^natTi(d,x)^44mSc, ^natTi(d,x)⁴⁶Sc, ^natTi(d,x)⁴⁷Sc, ^natV(d,x)⁴⁷Sc and ^natCr(d,x)⁴⁷Sc reactions were performed and the obtained calculation results were compared with the experimental cross-section data gathered from the literature. To understand whether there is a significant and consistent relationship between the experimental data and the calculation results, both have been plotted together and analyzed with the naked-eye. In addition, the calculations of the mean standardized deviation, the mean relative deviation, the mean ratio and the mean square logarithmic deviation were performed in order to evaluate the results numerically.

Effects of combining some theoretical models in the cross-section calculations of some alpha-induced reactions for natSb

In cases where it is not possible to obtain the cross-section values experimentally due to various factors, the importance of obtaining them with theoretical models has been explained in many studies available in the literature. In this context, the comparison of the cross-section values obtained by using the theoretical models with the experimental data will also be very beneficial for updating and developing these models. Existing studies, which also serve this purpose, have given inspiration to this study and it is aimed to examine the effects of the simultaneous use of the alpha optical model potentials and the level density models on the cross-section calculations for some alpha-particle-induced reactions on natural antimony. The effects of theoretical models on the cross-section calculations were investigated by comparing the obtained calculation results with the experimental data taken from the literature. The TALYS code, which is frequently preferred in the literature, was used in all calculations within the scope of this study. For the comparison of the calculated results with the experimental data, not only a visual analysis by graphing the outcomes, but also a mean-weighted-deviation calculation was used, and the findings were interpreted by accounting for both of them.

Effects of deuteron optical models on the cross-section calculations of deuteron induced reactions on natural germanium

A common feature of scientific studies is that when experimental observation data are not available, theoretical calculations are used to obtain information about the subject under investigation. In this context, many parameters and theoretical models have been developed that can be used in nuclear physics studies just as it is in other branches of sciences. It is intended that by doing so, theoretical models can be improved using recent experimental data while also learning about outcomes where experimental data is unavailable or difficult to access. Among the many theoretical models available, there are also deuteron optical models whose effects are examined in this study. The objective of this study is to examine the effects of different deuteron optical models on the cross-section calculations of deuteron induced reactions on natural germanium. The cross-section values of ^natGe(d,x)⁷⁰As, ^natGe(d,x)⁷¹As, ^natGe(d,x)⁷²As, ^natGe(d,x)⁷³As, ^natGe(d,x)⁷⁴As and ^natGe(d,x)⁷⁶As reactions were calculated using five deuteron optical models in the TALYS code's v1.95 for this aim, and the results were compared to the experimental data available in the database known as Experimental Nuclear Reaction Data (EXFOR) library. Graphics and quantitative analyses were also used to present the findings and interpretations of the outcomes.

Excitation functions for 209Bi reactions induced by threshold to 50 MeV energy alpha particles

Excitation functions for ²⁰⁹Bi(α,2n)²¹¹At, ²⁰⁹Bi(α,3n)²¹⁰At and ²⁰⁹Bi(α,4n)²⁰⁹At reactions were calculated using TALYS-1.95 nuclear code from threshold to 50 MeV by invoking suitable options for level densities, nucleon-nucleus optical model potentials and alpha optical model potentials. Statistical factors were used to verify the quality of matching between theoretical model calculations and the experimental data from the EXFOR database. The TTY of ²¹¹At calculated using the excitation function of ²⁰⁹Bi(a,2n)²¹¹At reaction is compared with existing experimental studies from literature The results of the present study are important for the validation of nuclear model approaches with increased predictive power for ²⁰⁹Bi(α,xn) reactions for the production of ²¹¹At.

Cross sections of 56Fe(n, p)56Mn, 55Mn(n, p)55Cr, 52Cr(n, p)52V, 56Fe(n, α)53Cr, 55Mn(n, α)52V and 52Cr(n, α)49Ti reactions using phenomenological level density models from threshold to 20 MeV

⁵⁶Fe(n,p)⁵⁶Mn, ⁵⁵Mn(n,p)⁵⁵Cr, ⁵²Cr(n,p)⁵²V, ⁵⁶Fe(n, α)⁵³Cr, ⁵⁵Mn(n, α)⁵²V and ⁵²Cr(n, α)⁴⁹Ti reactions are evaluated using four phenomenological nuclear level density models from reaction threshold to 20 MeV. The calculated data is compared with the experimental nuclear reaction data from EXFOR database. Statistical factors H, D and R are computed to identify the best fit. Level density parameters are adjusted for further improvement of the fitting. Back shifted Farmi-gas model gives a resemblance of neutron-induced ⁵⁶Fe, ⁵⁵Mn and constant temperature Fermi-gas model gives a closeness for ⁵²Cr reaction with our new parameter values.

Analysis of neutron induced (n,γ) and (n,2n) reactions on 232Th from reaction threshold to 20 MeV

Excitation functions for ²³²Th(n,γ) and ²³²Th(n,2n) reactions from reaction threshold to 20 MeV were calculated using TALYS-1.9 nuclear code by invoking suitable options for the level densities, optical model potentials, pre-equilibrium effects and γ-ray strength functions. In earlier studies, theoretical plots for ²³²Th(n,γ) and ²³²Th(n,2n) reaction cross-sections were obtained by using EMPIRE 3.2 and TALYS 1.9 codes with default parameters, however none of the reported plots could match with the corresponding experimental cross-sections reported in EXFOR data particularly between 14-20 MeV. The results of the present study reveal that by using a combination of specific input parameters in TALYS 1.9 code, the theoretical evaluation of the cross sections favour a higher pre-equilibrium rate for the harder spectrum. Moreover the estimated cross-sections match fairly well with the corresponding experimental data (EXFOR database) as well as with the evaluated data files (ENDF/VII.0, JENDL-4.0). The results of the present study are important for the validation of nuclear model approaches with increased predictive power for (n,xn) cross-sections and particularly for the application of thorium based fuel in Accelerator-Driven Sub-critical System.

An investigation of effects of level density models and gamma ray strength functions on cross-section calculations for the production of 90Y, 153Sm, 169Er, 177Lu and 186Re therapeutic radioisotopes via (n,γ) reactions

One of the methods used to treat different cancer diseases is the employment of therapeutic radioisotopes. Therefore, many clinical, theoretical and experimental studies are being carried out on those radioisotopes. In this study, the effects of level density models and gamma ray strength functions on the theoretical production cross-section calculations for the therapeutic radioisotopes 90Y, 153Sm, 169Er, 177Lu and 186Re in the (n,γ) route have been investigated. TALYS 1.9 code has been used by employing different level density models and gamma ray strength functions. The theoretically obtained data were compared with the experimental data taken from the literature. The results are presented graphically for better interpretation.

Theoretical calculations of production cross-sections for the 201Pb, 111In 18F and 11C radioisotopes at proton induced reactions

Production of radioisotopes that used in medical diagnosis and treatment are mostly based on the nuclear reactions. The cross-section data are important to understand nuclear reaction mechanisms. In this study TALYS 1.8 code has been used to calculate production cross-sections of ²⁰¹Pb, ¹¹¹In, ¹⁸F and ¹¹C radioisotopes at proton induced reactions. Constant Temperature Fermi Gas Model (CTFGM), Back Shifted Fermi Gas Model (BSFGM) and Generalised Super Fluid Model (GSM) have been employed as a level density models for computations. Relative variance calculations have been carried out to determine the best level density model. In addition to cross-section calculations, total activities of radioisotopes have been presented. Production cross-section calculation results have been compared with experimental data taken from Experimental Nuclear Reaction Database (EXFOR).

Investigation of gamma strength functions and level density models effects on photon induced reaction cross-section calculations for the fusion structural materials 46,50Ti, 51V, 58Ni and 63Cu

Scientists have been focused on fusion reactor studies to overcome the increasing energy demand. The materials, which have the potential to be used in fusion reactors must be resistant to the harmful effects of radiation in the manner of material itself. Selection of the appropriate materials to be used in nuclear reactors has a crucial importance to achieve the maximum efficiency and security. Ti, V, Ni and Cu are known as some of the constructional fusion materials. Existence of many knowledge about those materials provides countless advantages to the researchers and one of them is the cross-section, which basically means the probability of a nuclear reaction's occurrence. In addition to the cross-section, there exist some other parameters, which could be pointed as gamma strength function and level density models that affect the theoretical calculations. In this study, photon induced reaction cross-sections of ^46,50Ti, ⁵¹V, ⁵⁸Ni and ⁶³Cu target isotopes have been calculated by using TALYS 1.8 code with different gamma strength functions in the giant dipole resonance region. For gamma strength functions Kopecky-Uhl generalised Lorentzian Model, Brink-Axel Lorentzian Model, Hartree-Fock BCS tables, Hartree-Fock-Bogolyubov tables and Goriely's Hybrid Model have been employed. To appoint the best gamma strength function model, the relative variance calculations have been performed. Also, reaction cross-sections have been recalculated by using the best gamma strength function models through the different level density options. Constant Temperature Fermi Gas Model, Back Shifted Fermi Gas Model and Generalised Super Fluid Model have been employed for level density calculations. Experimental data for the investigated reactions have been taken from EXFOR library and used for comparisons of the obtained calculation results.

Evaluation of different production routes for the radio medical isotope ²⁰³Pb using TALYS 1.4 and EMPIRE 3.1 code calculations

(203)Pb radio-medical isotope has found great field of applications in nuclear medicine over the last decades. The previously measured excitation functions for the production of this isotope from different reactions were discussed, in order to confirm the most reasonable ones. Fitting curves were given for some reactions leading to the production of this isotope. The theoretical models TALYS 1.4, and EMPIRE 3.1 were used to construct the excitation functions for protons, deuterons, helium-3 and helium-4 induced reactions on Tl and Hg targets. The results of different models were compared with each other as well as with the collected experimental results, using the mean weighted deviation (F), and the relative variance (D) statistical parameters. Thick target yields were estimated, based on the discussed excitation functions, and compared with some measured values.

Uncertainty in cross-section calculations for reactions induced by neutrons with energy above 0.1 MeV

The uncertainty in the calculation of neutron induced reaction cross-sections using modern nuclear models and codes has been investigated. The cross-sections have been calculated with the help of the TALYS code and the modified ALICE code using different models for the calculation of nuclear level density. The experimental data from EXFOR for neutron induced reactions for nuclei from 27Al to 209Bi and incident neutron energies above 0.1 MeV have been used for the comparison with calculations. The results obtained give the possibility to find the best approaches for the cross-section calculation for nuclei from different mass ranges.

Investigation of nuclear model predictions for proton induced reaction cross-sections up to 150 MeV

An extensive analysis of the accuracy in the theoretical reproduction of experimental proton induced reaction cross-sections up to 150 MeV is presented. The predictive capabilities of different models for the description of the nuclear level densities as implemented in the TALYS code and in the modified ALICE code have been assessed by means of a systematic comparison of the theoretical results with experimental EXFOR data relative to target nuclei from 24Mg to 209Bi. The results obtained give the possibility to find the best approaches for the cross-section calculation for nuclei from different mass ranges and for different channels.

Theoretical calculations of the reaction cross-sections for proton-induced reactions on natural copper using ALICE-IPPE code

A theoretical study of the nuclear-reaction cross sections for proton-induced reactions on (63)Cu and (65)Cu was performed in the proton energy range from threshold values up to 50MeV. The produced nuclei were different isotopes of Zn, Cu, Ni, Co and Mn, some of which have important applications. The reaction cross-section calculations were performed using the ALICE-IPPE code, which depends on the pre-equilibrium compound nucleus model. This code is suitable for the studied energy and isotopic mass ranges. Approximately 14 excitation functions for the different reactions have been constructed from the calculated cross-section values. The excitation function curves for the proton reactions with natural copper targets have been constructed from those for enriched targets using the natural abundance of the copper isotopes. Comparisons between the calculated excitation functions with those previously experimentally measured are given whenever the experimental values were available. Some statistical parameters were introduced to control the quality of the fitting between both the experimental and the theoretical calculated cross-section values.

Evaluation of excitation functions of proton and deuteron induced reactions on enriched tellurium isotopes with special relevance to the production of iodine-124

Cross-section data for the production of medically important radionuclide (124)I via five proton and deuteron induced reactions on enriched tellurium isotopes were evaluated. The nuclear model codes, STAPRE, EMPIRE and TALYS, were used for consistency checks of the experimental data. Recommended excitation functions were derived using a well-defined statistical procedure. Therefrom integral yields were calculated. The various production routes of (124)I were compared. Presently the (124)Te(p,n)(124)I reaction is the method of choice; however, the (125)Te(p,2n)(124)I reaction also appears to have great potential.

Yield and excitation function measurements of some nuclear reactions on natural thallium induced by protons leading to the production of medical radioisotopes201Tl and203Pb

Excitation functions for201Pb,202mPb,203Pb and204mPb radionuclides which are formedviaproton induced reactions with natural thallium target have been measured from their respective threshold (Ethr) to 27.5 MeV using activation technique. Natural copper foils were used to monitor the cyclotron beam. The integral yields (MBq/μA h) of the produced radionuclides were calculated from the measured excitation functions. The optimum proton energy range for the production of203Pb with low amount of impurities is (16–10 MeV) after 5 h of EOB. The experimental cross-sections fornatTl(p,xn) reactions were compared with the cross-sections recommended by the IAEA and with earlier published data when it was possible.