Investigation of Neutron-Production Cross Sections of the Structural Fusion Material 181Ta for (α,xn) Reactions up to 150 MeV Energy

In this study, the theoretical neutron-production cross-sections produced by (α,xn) reactions (x = 3, 4, 5, 6, 7) for structural fusion material ¹⁸¹Ta in alpha-induced reactions have been investigated up to 150 MeV alpha incident energy. Also, neutron-emission spectra of ¹⁸¹Ta(α,xn) reactions have been investigated for incident alpha energies at 26.8 and 45.2 MeV. Reaction cross-sections as a function of alpha energy and neutron-emission spectra have been calculated theoretically using ALICE/ASH and TALYS 1.2 computer codes. The calculated results have been compared with the each other and experimental data existing in EXFOR database. The obtained results have been discussed and compared with the available experimental data and found agreement with each other.     

Alpha Production Cross Sections for Some Target Fusion Structural Materials up to 35 MeV

In the next century, because of the worldwide energy shortage, human life will badly be affected. Nuclear fusion energy is the remarkable solution to the rising energy challenges because it has the great potential for sustainability, economic and reliability. There have been many research and development studies to get energy from fusion. Moreover, the neutron induced reaction cross section data around 14–15 MeV are need to the design and development of nuclear fusion reactors. Thus, the working out the systematics of (n,α) reaction cross sections is very important and necessary for the definition of the excitation curves at around 14–15 MeV energy. In this study, neutron induced reaction cross sections for structural fusion materials such as Sc (Scandium), Co (Cobalt), Ni (Nickel), Cu (Copper), Y (Yttrium), Mo (Molybdenum), Zr (Zirconium) and Nb (Niobium) have been investigated for the (n,α) reactions. The new calculations on the excitation functions of ⁴⁵ Sc(n,a) ⁴² K, ⁵⁹ Co (n,a) ⁵⁶ Mn, ⁶² Ni(n,a) ⁵⁹ Fe, ⁶³ Cu(n,a) ⁶⁰ Co, ⁶⁵ Cu(n,a) ⁶² Co, ⁸⁹ Y(n,a) ⁸⁶ Rb, ⁹² Mo(n,a) ⁸⁹ Zr, ⁹⁸ Mo(n,a) ⁹⁵ Zr, ⁹² Zr(n,a) ⁸⁹ Sr, ⁹⁴ Zr(n,a) ⁹¹ Sr and ⁹³ Nb(n,a) ⁹⁰ Y reactions have been carried out up to 35 MeV incident neutron energies. In these calculations, the pre-equilibrium and equilibrium effects have been investigated. The pre-equilibrium calculations involve the new evaluated the geometry dependent hybrid model, hybrid model and the cascade exciton model. The equilibrium effects of the excitation functions for the investigated reactions are calculated according to the Weisskopf-Ewing model. Additionaly, in the present work, the (n,α) reaction cross sections have calculated by using evaluated empirical formulas developed by Tel et al. at 14–15 MeV energy. The calculated results have been discussed and compared with the available experimental data taken from EXFOR database.     

Calculations of Cross-Sections and Astrophysical S-factors for the (α,n) Reactions of Some Structural Fusion Materials

Structural material selection in design of fusion reactors is very crucial. These structural materials should satisfy the hard conditions such as high thermo-mechanical stresses, high heat loads and severe radiation damage without compromising on safety considerations. The materials such as titanium, vanadium and chromium are used in the construction of fusion reactors. Therefore, it is important to examine these materials. Obtained results from the nuclear reactions using structural materials can be used for developing of these structural materials. For this reason, in this study cross sections of the ⁴⁶Ti(α,n) ⁴⁹Cr, ⁵⁰Cr(α,n) ⁵³Fe and ⁵¹V(α,n) ⁵⁴Mn reactions have been calculated at 2–20 MeV energy range. In these theoretical calculations, the TALYS 1.8 and NON-SMOKER codes were used. Also, the astrophysical S-factors which describe the possibility of reaction in low energies were calculated. Results of our calculations were checked to the experimental data obtained from EXFOR database.     

Comparison of Level Density Models for the <Superscript>60,61,62,64</Superscript>Ni(p,n) Reactions of Structural Fusion Material Nickel from Threshold to 30 MeV

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 ⁶⁰Ni, ⁶¹Ni, ⁶²Ni and ⁶⁴Ni 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 ^60,61,62,64Ni reactions. The (p, n) reaction cross-section calculations for ^60,61,62,64Ni target nuclei were compared with each other and the experimental nuclear reaction data obtained from EXFOR database.     

Deuteron Induced (d,p) and (d,2p) Nuclear Reactions up to 50 MeV

Many studies have shown that the nuclear reactions of charged particles with nuclei are very important in many fields of nuclear physics. The interactions of deuterons with nuclei have been especially the subject of common research in the history of nuclear physics. Moreover, the knowledge of cross section for deuteron-nucleus interactions are required for various application such as space applications, accelerator driven sub-critical systems, nuclear medicine, nuclear fission reactors and controlled thermonuclear fusion reactors. Particularly, the future of controlled thermonuclear fusion reactors is largely dependent on the nuclear reaction cross section data and the selection of structural fusion materials. Finally, the reaction cross section data of deuteron induced reactions on fusion structural materials are of great importance for development and design of both experimental and commercial fusion devices. In this work, reaction model calculations of the cross sections of deuteron induced reactions on structural fusion materials such as Al (Aluminium), Ti (Titanium), Cu (Copper), Ni (Nickel), Co (Cobalt), Fe (Iron), Zr (Zirconium), Hf (Hafnium) and Ta (Tantalum) have been investigated. The new calculations on the excitation functions of ²⁷ Al(d,2p) ²⁷ Mg, ⁴⁷ Ti(d,2p) ⁴⁷ Sc, ⁶⁵ Cu(d,2p) ⁶⁵ Ni, ⁵⁸ Ni(d,2p) ⁵⁸ Co, ⁵⁹ Co(d,2p) ⁵⁹ Fe, ⁵⁸ Fe(d,p) ⁵⁹ Fe, ⁹⁶ Zr(d,p) ⁹⁷ Zr, ¹⁸⁰ Hf (d,p) ¹⁸¹ Hf and ¹⁸¹ Ta(d,p) ¹⁸² Ta have been carried out for incident deuteron energies up to 50 MeV. In these calculations, the equilibrium and pre-equilibrium effects for (d,p) and (d,2p) reactions have been investigated. The equilibrium effects are calculated according to the Weisskopf-Ewing (WE) Model. The pre-equilibrium calculations involve the new evaluated the Geometry Dependent Hybrid Model (GDH) and Hybrid Model. In the calculations the program code ALICE/ASH was used. The calculated results are discussed and compared with the experimental data taken from the literature.     

Calculation for Cross Section of (p,n) Reaction on Sixteen Targets in Energy Region up to 100 MeV

A semiempirical method based on the evaporation and exciton models is developed to calculate the cross section of the (p,n) reaction, in the mass number region 30≤A≤140, and incident proton energy E_p≤100 MeV, and the systematics of two parameters obtained. Using the formulas, the calculation for sixteen targets has been performed, the results of the calculation are in agreement with the measured data.     

Cross Sections Calculations of (d, t) Nuclear Reactions up to 50 MeV

In nuclear fusion reactions two light atomic nuclei fuse together to form a heavier nucleus. Fusion power is the power generated by nuclear fusion processes. In contrast with fission power, the fusion reaction processes does not produce radioactive nuclides. The fusion will not produce CO₂ or SO₂. So the fusion energy will not contribute to environmental problems such as particulate pollution and excessive CO₂ in the atmosphere. Fusion powered electricity generation was initially believed to be readily achievable, as fission power had been. However, the extreme requirements for continuous reactions and plasma containment led to projections being extended by several decades. In 2010, more than 60 years after the first attempts, commercial power production is still believed to be unlikely before 2050. Although there have been significant research and development studies on the inertial and magnetic fusion reactor technology, there is still a long way to go to penetrate commercial fusion reactors to the energy market. In the fusion reactor, tritium self-sufficiency must be maintained for a commercial power plant. Therefore, for self-sustaining (D–T) fusion driver tritium breeding ratio should be greater than 1.05. Working out the systematics of (d, t) nuclear reaction cross sections is of great importance for the definition of the excitation function character for the given reaction taking place on various nuclei at different energies. Since the experimental data of charged particle induced reactions are scarce, self-consistent calculation and analyses using nuclear theoretical models are very important. In this study, (d, t) cross sections for target nuclei ¹⁹F, ⁵⁰Cr, ⁵⁴Fe, ⁵⁸Ni, ⁷⁵As, ⁸⁹Y, ⁹⁰Zr, ¹⁰⁷Ag, ¹²⁷I, ¹⁹⁷Au and ²³⁸U have been investigated up to 50 MeV deuteron energy. The excitation functions for (d, t) reactions have been calculated by pre-equilibrium reaction mechanism. Calculation results have been also compared with the available measurements in literature.     

Cross-Section Calculations on Several Structural Fusion Materials for (γ,3n) Reactions in the Photon Energy Range of 20–110 MeV

In this study, photo-neutron cross-sections of (γ,3n) reactions for several structural fusion materials such as ⁵⁵Mn, ⁶⁵Cu, ⁹⁴Zr, ^98,100Mo, ¹⁸¹Ta and ¹⁸⁶W have been investigated in the incident photon energy range of 20–110 MeV. Theoretical cross-section calculations, based on theoretical nuclear reaction models, have been carried out using the PCROSS, EMPIRE 3.1 and TALYS 1.6 codes. EMPIRE 3.1 exciton, TALYS 1.6 two component exciton and TALYS 1.6 pre-equilibrium models have been used to calculate the pre-equilibrium photo-neutron cross-sections. For the equilibrium cross-section calculations, PCROSS Weisskopf–Ewing model has been preferred. The calculated results have been compared with each other and against the experimental nuclear reaction data (EXFOR). Except the ⁶⁵Cu(γ,3n)⁶²Cu reaction, all model equilibrium and pre-equilibrium cross-section calculations exhibit generally good agreement with the experimental values for all reactions used in this study. TALYS 1.6 two component exciton model can be recommended, if experimental photo-neutron cross-section data are not available or are unlikely to be produced because of the experimental difficulties.     

Prediction of the Cross Sections of p ~(11)C and d ~(11)C Reactions for Energy up to 25 MeV

~(11)C (half time is 20.3 min) is a proton-rich radioactive nucleus. The cross sections of p ~(11)C and d ~(11)C reactions were predicted in energy region up to 25 MeV. From the calculated results one can see some features of nuclear reactions of proton-rich radioactive nuclei. The calculated results also show that the experimental measurement to ~(11)C d reaction is more feasible than to ~(11)C p reaction at HI-13 tandem accelerator.     

Calculations of Excitation Functions of Some Structural Fusion Materials for (<Emphasis Type="Italic">n</Emphasis>, <Emphasis Type="Italic">t</Emphasis>) Reactions up to 50 MeV Energy

Fusion serves an inexhaustible energy for humankind. Although there have been significant research and development studies on the inertial and magnetic fusion reactor technology, there is still a long way to go to penetrate commercial fusion reactors to the energy market. 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. So, the working out the systematics of (n, t) reaction cross sections is of great importance for the definition of the excitation function character for the given reaction taking place on various nuclei at different energies. In this study, (n, t) reactions for some structural fusion materials such as ²⁷Al, ⁵¹V, ⁵²Cr, ⁵⁵Mn, and ⁵⁶Fe have been investigated. The new calculations on the excitation functions of ²⁷Al(n, t)²⁵Mg, ⁵¹V(n, t)⁴⁹Ti, ⁵²Cr(n, t)⁵⁰V, ⁵⁵Mn(n, t)⁵³Cr and ⁵⁶Fe(n, t)⁵⁴Mn reactions have been carried out up to 50 MeV incident neutron energy. In these calculations, the pre-equilibrium and equilibrium effects have been investigated. The pre-equilibrium calculations involve the new evaluated the geometry dependent hybrid model, hybrid model and the cascade exciton model. Equilibrium effects are calculated according to the Weisskopf–Ewing model. Also in the present work, we have calculated (n, t) reaction cross-sections by using new evaluated semi-empirical formulas developed by Tel et al. at 14–15 MeV energy. The calculated results are discussed and compared with the experimental data taken from the literature.     

Excitation Functions of Proton Induced Reactions on ~(52)Cr in the Energy up to 30 MeV

A set of proton optical potential parameters is obtained on chromium from threshold to 65.0 MeV based on the available experimental data, and the excitation functions were evaluated and calculated for ~(52)Cr(p,n), (p,p′),(p,α), (p,~3He), (p,d), (p,t), (p,2n), (p,np pn), (p,nα αn), (p,2p) and (p,3n) from respective threshold to 30.0 MeV.     

Calculation of Various Cross Sections for n ~(169)Tm Reaction in Energy Range up to 100 MeV

The calculated results show that the activation products ~(168, 167, 166, 165)Tm are important neutron monitor reaction products for n ~(169)Tm reaction in energy range up to 100 MeV.     

Theoretical Calculation of n ~(59)Co Reaction in Energy Region up to 100 MeV

A set of neutron optical potential parameters for ~(59)Co in energy region of 2～100 MeV was obtained based on concerned experimental data. Various cross sections of n ~(59)Co reactions were calculated and predicted. The calculated results show that the activation products ~(58,57)Co, ~(59)Fe, and ~(56)Mn are main neutron monitor reaction products for n ~(59)Co reaction in energy range up to 100 MeV. ~(54)Mn production reaction can be a promising neutron monitor reaction in the energy region from 30 to 100 MeV.     

Calculations of Various Cross Sections for n ~(63,65)Cu Reactions in Energy Region up to 70 MeV

A set of neutron optical potential parameters for ~(63, 65)Cu in energy region of 2～80 MeV was obtained with available experimental data. Various cross sections of n ~(63, 65)Cu reactions are calculated and predicted in the energy range up to 70 MeV.     

Cross Section Calculations of (n,2n) and (n,p) Nuclear Reactions on Germanium Isotopes at 14–15 MeV

Neutron incident reaction cross sections of Germanium isotopes (^70,72,74,76Ge) were investigated for the (n,2n) and (n,p) reactions around 14–15 MeV. Cross section calculations have been presented for ⁷⁰Ge(n,2n)⁶⁹Ge, ⁷²Ge(n,2n)⁷¹Ge, ⁷⁴Ge(n,2n)⁷³Ge, ⁷⁶Ge(n,2n)⁷⁵Ge, ⁷⁰Ge(n,p)⁷⁰Ga, ⁷²Ge(n,p)⁷²Ga, ⁷⁴Ge(n,p)⁷⁴Ga, and ⁷⁶Ge(n,p)⁷⁶Ga reactions. Theoretical calculations were performed with four different computer codes: ALICE/ASH for the Geometry Dependent Hybrid model, TALYS 1.6 for two component Exciton model, EMPIRE 3.2 Malta for Exciton model and PCROSS for Full Exciton model with the incident neutron energy up to 20 MeV. The (n,2n) and (n,p) reaction cross section calculations were compared with empirical formulas derived by several researchers and compared with the experimental data obtained from EXFOR database as well as with evaluated Nuclear data files (ENDF/B-VII.1: USA 2014). Results show good agreement between the theoretical calculations having a major importance in nuclear data evaluation calculations and the experimental data from literature.     

Evaluation of Activation Cross Sections for (n,2n) Reactions on Some Nuclei

The evaluations of activation cross sections of (n,2n) reaction for ~(58)Ni, ~(87)Rb, ~(89)Y, ~(90)Zr, ~(140)Ce and ~(169)Tm were performed in order to update the previous evaluated data. The cross sections are recommended based on the recent experimental data, especially the new measured results in CIAE. The present evaluated data are compared with other evaluated data.     

Calculations of n+~(112,120)Sn Reactions in the Energy Region up to 20 MeV

A set of optimal neutron optical potential parameter is obtained based on experimental data of total, nonelastic, elastic scattering cross sections and elastic scattering distribution. All cross sections of neutron induced reaction, γ-ray produced cross sections, angular distribution, energy spectrum and double differential cross sections are calculated and analyzed for n+112 120Sn at incident neutron energies below 20 MeV. All experimental data are taken from EXFOR library and other evaluated data from JENDL-3.     

Evaluation and Calculation of Activation Cross Sections for ~(158,159)Tb(n,2n), (n,3n), (n,γ) and (n,x) Reactions Below 20 MeV

Introduction ~(159)Tb is a rare-earth element. Its activation cross section is a good indicator for nuclear science and technology applications. However, the evaluated data are very scarce in several nuclear data libraries. The cross section for ~(159)Tb(n,2n)~(158)Tb reaction was one of the Coordinate Research Program of IAEA on activation cross     

Evaluation and Calculation of Activation Cross Sections for ~(169)Tm(n,2n), (n,3n), (n,γ) and (n,x) Reactions Below 20 MeV

Introduction ~(169)Tm is a rare-earth element. Its activation cross sections are a good indicator for nuclear science and technology applications. However, there are no evaluated data in several nuclear data libraries. The activation cross sections for ~(169)Tm(n,2n), (n,3n), (n,γ) and some emission charged particle (n,x) reactions below 20 MeV were evaluated and calculated on the basis of experimental and theoretical data.     

Evaluation and Calculation of Activation Cross Sections for ~(151,153)Eu(n,2n), (n,3n), (n,γ) and (n,x) Reactions below 20 MeV

Eu is a rare-earth element. Its activation cross section is important for nuclear science and technology applications. However, there are some discrepancies in several evaluated nuclear data libraries. The cross section for ~(151,153)Eu(n,2n) reactions were one of the Coordinate Research Programs of IAEA on activation cross sections