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Öğe Calculation of Cross-sections and Astrophysical S-Factors for Ni-62(alpha,n) and Ni-62(alpha,gamma) Reactions of Structural Fusion Material Nickel(Springer, 2016) Yildiz, Ercan; Aydin, AbdullahNickel is an important element in fusion reactor technologies and astrophysical applications. Therefore, the knowledge of astrophysical S-factors and cross-sections on nickel isotopes is needed. In this work, the cross sections of the Ni-62(alpha,n) and Ni-62(alpha,gamma) reactions have been calculated. The alpha capture cross sections was calculated up to 10 MeV. In these theoretical calculations, the TALYS 1.6 and NON-SMOKER codes were used. Also for the Ni-62(alpha,n) and Ni-62(alpha,gamma) reactions, we calculated the astrophysical S-factors that determine the probability of reaction in low energies. Results of our calculations were checked to the experimental data obtained from EXFOR database.Öğe Calculation of cross-sections and astrophysical s-factors for the 63 Cu(α,n) and 63 Cu(α,γ) reactions(E D P Sciences, 2015) Yildiz, Ercan; Aydin, Abdullah; Sarpun, Ismail Hakki; Tel, EyyupThe cross sections and astrophysical S-factors of the Cu-63(alpha,gamma) and Cu-63(alpha,n) reactions have been calculated. The radiative alpha capture reaction cross sections was calculated in the incident energy range of 3 to 10 MeV and the (alpha,n) reaction cross sections was calculated in the incident energy range of 7 and 16 MeV. In these theoretical calculations, the TALYS 1.6 and NON-SMOKER codes were used. Also for these reactions, it was calculated the astrophysical S-factors which describe the possibility of reaction in low energies. Obtained results were compared to the experimental data taken from EXFOR database.Öğe Calculations of Cross-Sections and Astrophysical S-factors for the (alpha,n) Reactions of Some Structural Fusion Materials(Springer, 2017) Yildiz, Ercan; Aydin, Abdullah; Sarpun, Ismail Hakki; Tel, EyyupStructural 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 Ti-46(alpha,n) Cr-49, Cr-50(alpha,n) Fe-53 and V-51(alpha,n) Mn-54 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.Öğe Comparison of fission barrier and level density models for (alpha,f) reaction of some heavy nuclei(Pergamon-Elsevier Science Ltd, 2014) Sarpun, Ismail H.; Aydin, Abdullah; Kaplan, Abdullah; Koca, Hulya; Tel, EyyupIn this work, alpha induced fission reactions for some heavy nuclei (Th-232, U-235, U-238, Np-237 and Pu-238) are calculated based on both fission barrier models and level density models by using the TALYS 1.2 code. The calculations are compared with experimental data which are available in EXFOR library. Sierk fission barrier model shows the best agreement with data among the five fission barrier models and also calculations show that there is no distinction in the level density models for the (alpha,f) reaction of the nuclei studied for atomic numbers larger than 230. (C) 2014 Elsevier Ltd. All rights reserved.Öğe Determination of (n,2n) Reaction Cross Sections for Some Nuclei with Asymmetry Parameter(Springer, 2010) Sarpun, İsmail Hakkı; Yalim, Hüseyin Ali; Ünal, Rıdvan; Oruncak, Bekir; Aydin, Abdullah; Kaplan, Abdullah; Tel, EyüpThe (n,2n) reaction cross sections for targets of Tl-203,Tl-205, Pb-204,Pb-206,Pb-207,Pb-208, Bi-209, Th-232 and U-238 were calculated both theoretically and semi-empirically. Theoretical calculations were done using two different computer codes: PCROSS computer code for the full exciton model and ALICE/ASH-2006 computer code for the geometry dependent hybrid (GDH) model with the incident neutron energy up to 25 MeV. Semi-empirical calculations were done using formulas derived by several researchers. The obtained results have been discussed and compared with the available experimental data taken from the literature. The different nuclear reaction program codes used in the present study show considerable differences depending upon the selected energy range. Especially PCROSS calculation results show a disagreement above the incident energy of about 16 MeV for all the studied nuclei. Moreover, even though the graphs qualitatively agree in shape, they differ in magnitude below 15 MeV.Öğe Determination of the effects of nuclear level density parameters on photofission cross sections of U-235 up to 20 MeV(E D P Sciences, 2017) Sarpun, Ismail Hakki; Aydin, Abdullah; Pekdogan, HakanThe level density models and level density parameters are two of important quantities for describing the properties of nuclei. Especially, the level density parameter has an important role as input in calculation of reaction cross sections. In this study, the cross sections on U-235(g,f) reaction were calculated for different level density models using the TALYS 1.6 code up to 20MeV gamma incident energies. First, it was determined the level density model that was the closest to the experimental data. Secondly, cross sections obtained for different level density parameters of this model were compared with experimental data from the EXFOR database. Thus it was determined the best level density parameter fit to experimental data.Öğe Determinations of fission cross-sections and fission yields from proton induced fission reactions of 232Th, 233,235,236,238U, 237Np and 239Pu(World Scientific Publ Co Pte Ltd, 2021) Sarpun, Ismail Hakki; Yalim, Huseyin Ali; Aydin, Abdullah; Tel, Eyyup; Akdeniz, Ferhan; Sahin, SelcanIn this work, the proton induced fission reaction cross-sections and fission yields are calculated for some actinides (Th-232, U-233,U-235,U-236,U-238, Np-237, and Pu-239) using the fission barrier models of the TALYS 1.95 code. Cross-sections and fission yield calculations are carried out up to 100 MeV incident proton energies. The calculation results are compared with the available experimental data in the EXFOR library. In addition, a relative variance analysis of fission barrier models was done to determine the fission barrier model whose results best matched with the experimental results. Among the fission barrier models, the best agreement with the experimental data is obtained from the rotating-finite-range fission barrier model calculation for the (p,f) reaction of the studied nuclei having the atomic mass number larger than 230. On the other hand, fission barrier heights for the studied reactions are determined using the same models.Öğe Double differential cross section calculations of (n,p) reactions on 27Al and 24Mg targets(EDP Sciences, 2024) Sarpün, Ismail Hakki; Tel, Eyyup; Aydin, Abdullah; Yildirir, UnalIn structural fusion material research, double differential sections are necessary to determine heating and damage due to secondary particles that may occur in structural materials. Therefore, in this study, the double differential proton emission cross sections of 27Al and 24Mg target nuclei were calculated theoretically with the TALYS nuclear reaction code at 14 MeV neutron energy. The calculated values were compared with existing experimental data in the EXFOR library. Additionally, the contribution of direct, compound and preequilibrium reactions in theoretical calculations was investigated. © The Authors.Öğe Double differential light charged particle emission cross sections for some structural fusion materials(E D P Sciences, 2017) Sarpun, Ismail Hakki; Aydin, Abdullah; Tel, EyyupIn fusion reactors, neutron induced radioactivity strongly depends on the irradiated material. So, a proper selection of structural materials will have been limited the radioactive inventory in a fusion reactor. First-wall and blanket components have high radioactivity concentration due to being the most flux-exposed structures. The main objective of fusion structural material research is the development and selection of materials for reactor components with good thermo-mechanical and physical properties, coupled with low-activation characteristics. Double differential light charged particle emission cross section, which is a fundamental data to determine nuclear heating and material damages in structural fusion material research, for some elements target nuclei have been calculated by the TALYS 1.8 nuclear reaction code at 14-15 MeV neutron incident energy and compared with available experimental data in EXFOR library. Direct, compound and pre-equilibrium reaction contribution have been theoretically calculated and dominant contribution have been determined for each emission of proton, deuteron and alpha particle.Öğe Double Differential Proton Emission Cross Sections for Structural Fusion Materials Mg-24(Amer Inst Physics, 2018) Demirelli, Gozde; Sarpun, Ismail H.; Oruncak, Bekir; Tel, Eyyup; Aydin, AbdullahIn this study, double differential proton emission cross sections of 24Mg target nuclei have been theoretically calculated by the TALYS 1.8 code at 14 MeV neutron incident energy. Theoretical calculated cross sections were compared with available experimental data in EXFOR nuclear data library. Furthermore, in theoretical calculations direct, compound and pre-equilibrium reaction contribution have been investigated. Theoretical and experimental values are in good agreement for all given emission angles.Öğe Equilibrium and pre-equilibrium emissions in proton-induced reactions on Tl-203,Tl-205(Indian Acad Sciences, 2009) Kaplan, Abdullah; Aydin, Abdullah; Tel, Eyüp; Sarer, BaşarIn this study, the excitation functions for the reactions Tl-203(p, n)Pb-203, Tl-205(p, 3n)Pb-203, Tl-203(p, 2n)Pb-202, Tl-205(p, 4n)Pb-202, Tl-203(p, 3n)Pb-201, Tl-205(p, 5n)Pb-201, Tl-203(p, 4n)Pb-200 and Tl-205(p, 6n)Pb-200 have been calculated using pre-equilibrium and equilibrium reaction mechanisms. Calculated results based on hybrid model, geometry-dependent hybrid model and cascade-exciton model have been compared with the experimental data.Öğe The Equilibrium and Pre-equilibrium Triton Emission Spectra of Some Target Nuclei for (n,xt) Reactions up to 45 MeV Energy(Springer, 2010) Tel, Eyüp; Kaplan, Abdullah; Aydin, Abdullah; Özkorucuklu, Suat; Büyükuslu, Halim; Yıldırım, GürcanAlthough 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, working out the systematics of (n,t) reaction cross sections and triton emission differential data are important for the given reaction taking place on various nuclei at different energies. In this study, (n,xt) reactions for some target nuclei as (16)O, (27)Al, (59)Co and (209)Bi have been investigated up to 45 MeV incident neutron energy. In the calculations of the triton emission spectra, the pre-equilibrium and equilibrium effects have been used. The calculated results have been compared with the experimental data taken from the literature.Öğe The equilibrium and preequilibrium neutron-emission spectra of some structural fusion materials for (n, xn) reactions up to 16 MeV energy(Maik Nauka/Interperiodica/Springer, 2009) Kaplan, Abdullah; Tel, Eyyüp; Aydin, AbdullahIn this study, neutron-emission spectra produced by (n, xn) reactions for some structural fusion materials as (27)Al, (51)V, (52)Cr, (55)Mn, and (56)Fe have been investigated by a neutron beam up to 16 MeV. Multiple preequilibrium mean-free-path constant from internal transition and the preequilibrium and equilibrium level-density parameters have been investigated for some (n, xn) neutron-emission spectra calculated in this study. Preequilibrium neutron-emission spectra were calculated by using new-evaluated hybrid model and geometry-dependent hybrid model, full-exciton model, and cascade-exciton model. The reaction equilibrium component was calculated by Weisskopf-Ewing model. The obtained results have been discussed and compared with the available experimental data and found agreement with each other.Öğe Investigation of Deuteron Emission Spectra at 62 MeV Proton Incident Energy(Springer, 2010) Aydin, Abdullah; Türeci, Gökhan; Tel, Eyüp; Kaplan, AbdullahIn this study, deuteron emission cross sections for (27)Al, (54,56)Fe, (89)Y, (120)Sn, (197)Au, (208)Pb and (209)Bi target nuclei have been calculated at 62 MeV proton incident energy. In these calculations, the pre-equilibrium and equilibrium effects have been investigated. The pre-equilibrium calculations involve the geometry dependent hybrid model and hybrid model. Equilibrium effects are calculated according to the Weisskopf-Ewing model. The calculated results are compared with the experimental data taken from the literature and found to be in good agreement.Öğe Investigation of gamma-ray attenuation coefficients for solid boronized 304L stainless steel(Pergamon-Elsevier Science Ltd, 2021) Araz, Sule Ocak; Gumus, Hasan; Bayca, Salih Ugur; Aydin, AbdullahIn this study, mass attenuation coefficient (mu/rho) and half value layer (HVL) at Eu-152 and Co-60 energies were used in measuring attenuation coefficients of the solid boronized AISI 304L stainless steel at 950 degrees C for 2, 4, 6 and 8 h. The experimental mass attenuation coefficients, mu/rho, and HVL for these materials were compared to theoretical values obtained with WinXCOM. At the same time a new boriding agent (Baybora (R)-1) also developed for solid boriding method was used. The effects of boron layer size on radiation attenuation of boronized composites were evaluated in relation with gamma-ray transmission and the results of the experiments were interpreted. It could be understood that increased of boron layer in AISI 304L causes of increases in the attenuation coefficient values. The measured values agree with the theoretical values. The interaction parameters for selected samples have been computed and provided in the extended energy range 10(-3)-10(4) MeV. The shielding properties prepared stainless steel have also been compared with standard concretes as well as with the standard shielding stainless steel. It is found that the prepared stainless steel is the better shielding substitute to the conventional concretes as well as other standard shielding stainless steel. So, submicron size boron layer used composite materials are more convenient than micron size boron used composite materials as radiation shielding materials for nuclear applications.Öğe Investigation of Nucleon Mean Free Path Dependence in Tritium Emission Spectra Produced by Proton Induced Reactions at 62 MeV(Springer, 2010) Yalim, Hueseyin Ali; Aydin, Abdullah; Sarpun, Ismail Hakki; Unal, Ridvan; Oruncak, Bekir; Kaplan, Abdullah; Tel, EyyupThis study aims on the effect of nucleon mean free path on differential cross sections of tritium-emission spectra for (p, H-3) reactions on Al-27, Fe-54,Fe- 56, Y-89, Sn-120, Au-197, Pb-208 and Bi-209 induced by 62 MeV protons in the pre-equilibrium reaction mechanisms. The pre-equilibrium calculations were carried out by using the geometry dependent hybrid model. The calculated results are compared with experimental data existing in literature and found to be in good agreement. Furthermore, using different multiplication factor for the mean free path in the calculation changes the differential cross sections of tritium emission spectra.Öğe Investigation of the (n, p) reaction cross-sections of some nuclei in the rare-earth elements for an incident energy range of 8-24 MeV(Iop Publishing Ltd, 2007) Aydin, Abdullah; Tel, Eyüp; Sarer, BaşarIn this study, the (n, p) reaction cross-sections of some target nuclei in the rare-earth elements have been investigated for an incident energy range of 8 - 24 MeV. In these calculations, the geometry-dependent hybrid model and the cascade exciton model including the effects of pre-equilibrium have been used. The full exciton model has also been used to investigate the pre-equilibrium direct effects. All calculated results have been compared with experimental data. In addition, the ratios of experimental ( n, p) cross-sections to calculated cross-sections using empirical and semi-empirical formulae have been calculated.Öğe Investigation of the effects of nuclear level density parameters on the cross sections for the U-234(gamma,f) reaction(E D P Sciences, 2015) Pekdogan, Hakan; Aydin, Abdullah; Sarpun, Ismail HakkiIn this study, we have investigated the effects of nuclear level density parameters on the cross sections for the U-234(gamma,f) reaction up to 20 MeV. The cross sections on U-234(gamma,f) reaction were calculated for different level density models using the TALYS 1.6 code. First, it was determined the level density model that was the closest to the experimental data. Secondly, cross sections obtained for different level density parameters of this model were compared with experimental data from the EXFOR database. Thus it was determined the best level density parameter fit to experimental data.Öğe Investigation of the nuclear structure of the Be, Cr and Cu isotopes(Pergamon-Elsevier Science Ltd, 2009) Tel, Eyyüp; Baldık, Rıdvan; Aytekin, Hüseyin; Aydin, AbdullahThe Root-Mean-Square (RMS) nuclear charge, neutron and proton radii, charge, neutron and proton densities, neutron skin thickness and total binding energy per particle were calculated using the Hartree-Fock method with Skyrme forces for the chromium (Cr), copper (Cu) and beryllium (Be) isotopes. The obtained results were compared with the experiment. Additional to these calculations the initial neutron and proton exciton numbers for Cr-52 isotope were also calculated. These exciton numbers can be used for pre-equilibrium proton induced (p, xn) reactions on Cr-52 isotope. (C) 2009 Elsevier Ltd. All rights reserved.Öğe Neutron Emission Spectra of Some Structural Fusion Materials at 26.8 and 45.2 MeV Alpha Incident Energies(Springer, 2010) Kaplan, Abdullah; Aydin, Abdullah; Tel, Eyüp; Büyükuslu, HalimIn this study, neutron-emission spectra produced by (alpha,xn) reactions for some structural fusion materials such as Al-27, Cr-53, Fe-56 and Ni-58,Ni-60,Ni-62 have been investigated. Hybrid model, geometry dependent hybrid model and full exciton model have been used to calculate the pre-equilibrium neutron-emission spectra. For the reaction equilibrium component, Weisskopf-Ewing model calculations have been preferred. The mean free path parameter's effect for (alpha,xn) neutron-emission spectra has been examined. The obtained results have been discussed and compared with the available experimental data and found agreement with each other.
