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(3He,xn) Reaction Cross-Section Calculations for the StructuralFusion Material 181Ta in the Energy Range of 14–75 MeV
(Springer, 2014) Kaplan, A.; Capali, V.; Ozdogan, H.; Aydin, A.; Tel, E.; Sarpun, I. H.
The theoretical neutron-production cross-sections produced by Ta-181(He-3,xn)Re184-x reactions (x = 1-7) for structural fusion material Ta-181 in He-3-induced reactions have been performed in the incident He-3 energy range of 14-75 MeV. Reaction cross-sections, based on theoretical pre-equilibrium nuclear reaction models, have been calculated theoretically by means of the TALYS 1.6 two component exciton, EMPIRE 3.1 exciton, ALICE/ASH geometry dependent hybrid (GDH) and ALICE/ASH hybrid models. The neutron-production cross-section results of the models have been compared with the each other and against the experimental nuclear reaction data (EXFOR). Except the Ta-181(He-3,2n)Re-182 and Ta-181(He-3,7n)Re-177 reactions, the ALICE/ASH cross-section calculations show generally agreement with the experimental values for all reactions used in this study. The ALICE/ASH-GDH model can be suggested, if the experimental data are unavailable or are improbably to be produced because of the experimental troubles.
Calculation of 14-15 MeV (n, d) reaction cross sections using newly evaluated empirical and semi-empirical systematics
(Springer, 2008) Aydin, A.; Tel, E.; Kaplan, A.
In this study, we have investigated the asymmetry term effect for the (n, d) reaction cross sections at 14-15 neutron incident energy. It has been discussed the odd-even effect and the pairing effect considering binding energy systematic of the nuclear shell model for the new experimental data and new cross section formulae developed by Tel et al. for (n, d) reactions. We have determined different parameter groups by the classification of nuclei into even-even, even-odd and odd-even for (n, d) reactions cross sections. The obtained empirical and semi-empirical formulae by fitting two parameters for (n, d) reactions were given. By using the new cross sections formulae for (n, d) reactions the obtained results have been discussed and compared with the available experimental data.
Calculation of Equilibrium and Pre-equilibrium He-4-Emission Spectra at 62 MeV Proton Incident Energy
(Springer, 2011) Aydin, A.; Tel, E.; Sahan, M.
In this study, the He-4-emission cross sections for Al-27, Fe-54,Fe-56, Au-197, Pb-208 and Bi-209 target nuclei have been calculated at 62 MeV proton energy. In these calculations, the pre-equilibrium effects have been investigated. The pre-equilibrium calculations involve the geometry dependent hybrid model and hybrid model. A comparison with theoretical calculations (ALICE/ASH) has been performed and the empirical formulas for the He-4-emission cross sections produced at 62 MeV proton energy have been derived.
Calculations of Double Differential Deuteron Emission Cross Sections at 62 MeV Proton Induced Reactions
(Springer, 2013) Aydin, A.; Sarpun, I. H.; Kaplan, A.; Tel, E.
In this study, double differential deuteron emission cross sections for Al-27, Fe-54,Fe-56, Au-197, Pb-208 and Bi-209 target nuclei have been calculated by the TALYS code at 62 MeV proton energy. The use of TALYS involved calculations by the pre-equilibrium exciton model and the Hauser-Feshbach model. The calculated double differential cross sections have been compared with the experimental data taken from the literature.
Calculations of Double-Differential Neutron Emission Cross Sections for Be-9 Target Nucleus at 14.2 MeV Neutron Energy
(Springer, 2015) Sahan, M.; Tel, E.; Sahan, H.; Kara, A.; Aydin, A.; Kaplan, A.; Yildiz, E.
In this study, we investigated neutron-emission spectra induced by (n,xn) nuclear reactions for the Be-9 structural fusion material at 14.2 MeV neutron energy. We calculated double-differential cross sections () with ALICE-2011 codeor the angles of 30A degrees, 60A degrees, 90A degrees, 120A degrees, and 150A degrees. Hybrid Monte Carlo simulation model have been used to calculate the double differential emission spectra for these different angles. The obtained results were compared with the measured data taken from EXFOR library. The results show an acceptable agreement.
Calculations of double-differential triton emission cross sections at 62-MeV proton-induced reactions
(Pleiades Publishing Inc, 2014) Aydin, A.; Sarpun, I. H.; Kaplan, A.
Double-differential cross sections (d (2) sigma/d Omega dE >) have been calculated and analyzed for triton production in proton-induced reactions on Al-27, Fe-54,Fe-56, Au-197, and Pb-208 target nuclei at incident energy of 62 MeV. Calculations of double-differential cross sections have been performed using nuclear models implemented in the TALYS 1.2 code. The calculated results of the double-differential cross sections for triton emission have been compared with the existing experimental data.
Calculations of proton-induced neutron production cross sections on Th-232 up to 1.6 GeV
(Amer Nuclear Society, 2006) Sarer, B.; Günay, M.; Aydin, A.; Tel, E.; Arasoğlu, A.
The Th-232(p, xn) and Th-232(p, np) cross sections for incident proton energies in the range of 10 to 1600 MeV have been calculated by using a cascade-exiton model (CEM) combining essential features of the exciton model and intranuclear cascade models. The level density parameter effects are investigated. The calculation results are compared with the available measured data.
Comparison of Level Density Models for the Ni-60,Ni-61,Ni-62,Ni-64(p, n) Reactions of Structural Fusion Material Nickel from Threshold to 30 MeV
(Springer, 2015) Aydin, A.; Pekdogan, H.; Kaplan, A.; Sarpun, I. H.; Tel, E.; Demir, B.
The knowledge of level density for reaction cross-section calculations are needed for various applications such as fission and fusion reactor design, accelerator driven sub-critical systems, nuclear medicine, neutron capture and astrophysics. In this study, the excitation functions for (p, n) reactions from reaction threshold to 30 MeV proton incident energy on Ni-60, Ni-61, Ni-62 and Ni-64 isotopes were calculated using TALYS 1.6 nuclear code involving the level density models. This is of importance to the validation of nuclear model approaches with increased predictive power. There are several models of level density that can be used to predict cross-section. In this work, the (p, n) cross-sections would be calculated using three different model of level density, such as constant temperature model, back-shifted fermi gas model and generalized superfluid model on Ni-60,Ni-61,Ni-62,Ni-64 reactions. The (p, n) reaction cross-section calculations for Ni-60,Ni-61,Ni-62,Ni-64 target nuclei were compared with each other and the experimental nuclear reaction data obtained from EXFOR database.
Double Differential Cross Section and Stopping Power Calculations of Light Charged Particle Emission for the Structural Fusion Materials Cr-50,Cr-52
(Springer, 2015) Demir, B.; Sarpun, I. H.; Kaplan, A.; Capali, V.; Aydin, A.; Tel, E.
Double differential cross section is a fundamental value to determine nuclear heating and material damages in structural fusion material research. In this study, double differential light charged particle emission cross sections for Cr-50,Cr-52 target nuclei have been calculated by the TALYS 1.6 code at 14.8 MeV incident neutron energy. Penetrating distance and stopping powers have been calculated for the alpha, deuteron and proton particles, taking into consideration all possible reactions in Cr-50,Cr-52 for incident energies of 0.5-22.2 MeV using GEANT4 calculation code. The compound nucleus formation process dominates the emission of proton and alpha particles. Direct reaction contribution becomes dominant in higher particle emission energies. The calculated double differential cross sections have been compared with the available experimental data taken from the literature.
The Effect of the Deformation Parameter on the Cross Sections for Reactions: Pd-110(d,n)Ag-111 and Pd-110(d, 2n)(110m) Ag
(Maik Nauka/Interperiodica/Springer, 2018) Boyukata, M.; Sarpun, I. H.; Aydin, A.
In this study, we focused on the effects of the deformation parameter on the cross sections. First, the deformation parameters of target nucleus Pd-110 was determined within the interacting boson model (IBM). Later this parameter was used in the TALYS-1.8 code to calculate the cross sections of the Pd-110(d,n)Ag-111 and Pd-110(d, 2n)(110m) Ag reactions. Moreover, other deformation parameters obtained RIPL-3 and TALYS default were used for the cross section calculation. The calculated results were compared with the experimental nuclear reaction data from EXFOR.
The effect of the initial exciton numbers on Fe-54,Fe-56(p, xp) Pre-Equilibrium Reactions
(Maik Nauka/Interperiodica/Springer, 2011) Bolukdemir, M. H.; Tel, E.; Aydin, A.; Okuducu, S.; Kaplan, A.
In pre-equilibrium nuclear reactions, the geometry-dependent hybrid model is applied with the use of the neutron and proton densities to investigate the effect of initial exciton numbers on the nucleon emission spectra. The initial exciton numbers calculated with the theoretical neutron and proton densities have been obtained within the Skryme-Hartree-Fock method with SKM* and SLy4 forces on target nuclei in the Fe-54,Fe-56(p, xp) reaction at 61.5-MeV incident proton energy by using a new calculationmethod of Tel et al. Also, the differences between the initial exciton numbers for protons and neutrons as a function of nuclear radius, focusing on systematic discrepancies correlated to differences in the proton and neutron densities have been investigated.
Excitation Functions Calculations of the Charged Particle-Induced Nuclear Reactions on the Be-9 Target
(Springer, 2017) Tel, E.; Gok, A. A.; Sahan, M.; Sarpun, I. H.; Kavun, Y.; Aydin, A.
In this study, calculation of charged particles induced nuclear reactions of beryllium (Be-9) target nuclei have been investigated in the incident proton and alpha at energy range from threshold to 50 MeV. The excitation functions for Be-9 target nuclei reactions have been calculated by using PCROSS nuclear reaction calculation code. Weisskopf-Ewing model for equilibrium, calculations and the full exciton and cascade exciton models for pre-equilibrium calculations were used. Also, the semi-empirical calculations for (p,alpha) reactions have been done by using cross section formula updated with new coefficient developed by Tel et al. (Pramana Indian Acad Sci 74(6):931, 2010). The calculated results were compared with the experimental data for different energy levels ranging from 0.00 to 9.65 MeV taken from the literature.
Excitation Functions of Some Neutron Production Targets on (d,2n) Reactions
(Springer, 2010) Kaplan, A.; Buyukuslu, H.; Aydin, A.; Tel, E.; Yildirim, G.; Bolukdemir, M. H.
Deuterons are weakly bound nuclei which easily undergo break up reactions. This is well known at low energies, around 10 MeV, where deuteron beams have been used to produce neutrons very efficiently. These neutrons have a widely application field such as fission energy production and hybrid reactor systems. In this study, neutron emission cross sections produced by (d,2n) reactions for spallation neutron targets such as Cr-52, Fe-56, Ni-60,Ni-62,Ni-64, Cu-63,Cu-65, W-182,W-183,W-184,W-186, Th-232, U-235 and U-238 have been investigated. Hybrid model and geometry dependent hybrid model were used to calculate the pre-equilibrium neutron-emission cross sections. For the reaction equilibrium process, Weisskopf-Ewing model calculations were selected. The obtained results have been discussed and compared with the available experimental data and found agreement with each other.
Improved Formula for (n,He-3) Fusion Reactions Cross Sections Using Optical Model
(Springer, 2010) Bolukdemir, M. H.; Tel, E.; Akti, N. N.; Aydin, A.; Okuducu, S.
Non-elastic cross-sections have been calculated by using optical model for (n, He-3) reactions at 14-15 MeV energy. The new empirical formula including optical model non-elastic effects by fitting two parameters for the (n, He-3) reaction cross-sections have been suggested. The excitation function character and reaction Q-values depending on the asymmetry term effect for the (n, He-3) reaction have been investigated. The obtained cross-section formula with new coefficients has been compared with the experimental data and the other fitting formulae existed in the literature and discussed. It has seen that the fit of new formula in this paper is greatly improved with the experimental data.
An Investigation for Ground State Features of Some Structural Fusion Materials
(Springer, 2011) Aytekin, H.; Tel, E.; Baldik, R.; Aydin, A.
Environmental concerns associated with fossil fuels are creating increased interest in alternative non-fossil energy sources. Nuclear fusion can be one of the most attractive sources of energy from the viewpoint of safety and minimal environmental impact. When considered in all energy systems, the requirements for performance of structural materials in a fusion reactor first wall, blanket or diverter, are arguably more demanding or difficult than for other energy system. The development of fusion materials for the safety of fusion power systems and understanding nuclear properties is important. In this paper, ground state properties for some structural fusion materials as Al-27, V-51, Cr-52, Mn-55, and Fe-56 are investigated using Skyrme-Hartree-Fock method. The obtained results have been discussed and compared with the available experimental data.
Investigation of 14-15 MeV (n, t) reaction cross-sections by using new evaluated empirical and semi-empirical systematic formulas
(Springer, 2008) Tel, E.; Aydin, A.; Kaplan, A.; Sarer, B.
In the hybrid reactor, tritium self-sufficiency must be maintained for a commercial power plant. For self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. Working out the systematics of (n, t) reaction cross-sections are of great importance for the definition of the excitation function character for the given reaction taking place on various nuclei at energies up to 20 MeV. In this study we have investigated asymmetry term effect for the (n, t) reaction cross-sections at 14-15 neutron incident energy. It has been discussed the odd-even effect and the pairing effect considering binding energy systematic of the nuclear shell model for the new experimental data and new cross-sections formulas (n, t) reactions developed by Tel et al. We have determined a different parameter groups by the classification of nuclei into even-even, even-odd and odd-even for (n, t) reactions cross-sections. The obtained empirical and semi-empirical formulas by fitting two parameter for (n, t) reactions were given. All calculated results have been compared with the experimental data and the other semi-empirical formulas.
Investigation of cross sections of reactions used in neutron activation analysis
(Carl Hanser Verlag, 2011) Tel, E.; Sahan, M.; Ugur, F. A.; Sahan, H.; Aydin, A.
In this study, neutron incident reaction cross sections for some target nuclei such as Mg-24, Al-27, Si-28, Fe-56, and Cu-63 used in neutron activation analysis have been investigated. The new calculations on the excitation functions of Mg-24(n, p)Na-24, Al-27(n, p)Mg-27, Al-27(n, alpha)Na-24, Si-28(n, p)Al-28, Fe-56(n, p)Mn-56, and Cu-63(n,2n)Cu-62 reactions have been carried out for incident neutron energies up to 20 MeV. In these calculations, the pre-equilibrium and equilibrium effects have been investigated. The pre-equilibrium calculations involve the new geometry dependent hybrid model and the full exciton model. Equilibrium effects are calculated according to the Weisskopf-Ewing model. In the present work, reaction cross-sections have been calculated by using empirical formulas developed for energies of 14-15 MeV. The calculated results are discussed and compared with the experimental data taken from the EXFOR database.
Investigation of Lead Target Nuclei Used on Accelerator-Driven Systems for Tritium Production
(Springer, 2012) Tel, E.; Aydin, A.
High-current proton accelerators are being researched at Los Alamos National Laboratory and other laboratories for accelerator production of tritium, transmuting long-lived radioactive waste into shorter-lived products, converting excess plutonium, and producing energy. These technologies make use of spallation neutrons produced in (p,xn) and (n,xn) nuclear reactions on high-Z targets. Through (p,xn) and (n,xn) nuclear reactions, neutrons are produced and are moderated by heavy water. These moderated neutrons are subsequently captured on He-3 to produce tritium via the (n,p) reaction. Tritium self-sufficiency must be maintained for a commercial fusion power plant. Rubbia succeeded in a proposal of a full scale demonstration plant of the Energy Amplifier. This plant is to be known the accelerator-driven system (ADS). The ADS can be used for production of neutrons in spallation neutron source and they can act as an intense neutron source in accelerator-driven subcritical reactors, capable of incinerating nuclear waste and of producing energy. Thorium and Uranium are nuclear fuels and Lead, Bismuth, Tungsten are the target nuclei in these reactor systems. The spallation targets can be Pb, Bi, W, etc. isotopes and these target material can be liquid or solid. Naturally Lead includes the Pb-204 (%1.42), Pb-206 (%24.1), Pb-207 (%22.1) and Pb-208 (%52.3) isotopes. The design of ADS systems and also a fusion-fission hybrid reactor systems require the knowledge of a wide range of better data. In this study, by using Hartree-Fock method with an effective nucleon-nucleon Skyrme interactions rms nuclear charge radii, rms nuclear mass radii, rms nuclear proton, neutron radii and neutron skin thickness were calculated for the Pb-204,Pb- 206,Pb- 208 isotopes. The calculated results have been compared with those of the compiled experimental and theoretical values of other studies.
Investigation of neutron skin effect with density dependence by using a new calculation method for initial exciton numbers on pre-equilibrium reactions
(Iop Publishing Ltd, 2009) Tel, E.; Bolukdemir, M. H.; Okuducu, S.; Aydin, A.; Kaplan, A.
In this study, we investigated the pre-equilibrium effect by using a new evaluated geometry-dependent hybrid model and a neutron skin effect with density dependence for the (204,206,207)Pb(p, xn) reaction at 25.5MeV incident proton energy. We calculated the initial exciton numbers obtained from the modified Skyrme force based on fitting the fission barriers of heavy deformed nuclei (SKM*) and SLy4 for proton induced reaction on target nuclei (204,206,207)Pb. We calculated, by using a new calculation method, the initial neutron and proton exciton numbers for (204,206,207)Pb from the neutron and proton density and we investigated the shell effect by using an effective nucleon-nucleon interaction with Skyrme force. We also compared the geometry-dependent hybrid model (GDH), newly evaluated with the initial exciton number calculations of the neutron emission spectra of the (204,206,207)Pb(p, xn) reaction, with the values reported in the literature at 25.5MeV incident proton energy. The obtained results were investigated and compared with the pre-equilibrium calculations and experimental results.
Investigation of Some Stellar Iron Group Fusion Materials for (n, p) Reactions
(Springer, 2012) Sahan, M.; Tel, E.; Aydin, A.; Yegingil, Ilhami
In this study, we present the results of a careful analysis of cross sections of some important iron (Fe) group target elements (20 a parts per thousand currency sign Za parts per thousand currency sign28) for astrophysical (n, p) reactions such as Si, Ca, Sc, Ti, V, Cr, Fe, Co and Ni used in neutron activation analysis have been investigated. The new calculations on the excitation functions of (28) Si(n, p) (28) Al, (29) Si(n, p) (29) Al, (42) Ca(n, p) (42) K, (45) Sc(n, p) (45) Ca, (46) Ti(n, p) (46) Sc, (51) V(n, p) (51) Ti, (52) Cr(n, p) (52) V, (53) Cr(n, p) (53) V, (54) Fe(n, p) (54) Mn, (57) Fe(n, p) (57) Mn, (59) Co(n, p) (59) Fe, (58) Ni(n, p) (58) Co and (60) Ni(n, p) (60) Co reactions have been carried out up to 25 MeV incident neutron energy. In these calculations, the pre-equilibrium and equilibrium effects have been investigated. Equilibrium effects are calculated according to the Weisskopf-Ewing model. The pre-equilibrium calculations involve the geometry dependent hybrid model, hybrid model and equilibrium model. Also in the present work, these reaction cross-sections have been calculated by using evaluated empirical formulas developed by Tel et al. at 14.7 MeV energy. The calculations are compared with existing experimental data as well as with evaluated data files (Experimental Nuclear Reaction Data (EXFOR). According to these calculations, we assume that these model calculations can be applied to some heavy elements, ejected into interstellar medium by dramatic supernova events.

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