Deuteron-induced activation cross-sections on natural copper up to 24 MeV

Activation cross-sections of ^natCu(d,x)^62,65Zn,⁶⁴Cu,^60g+mCo,⁵⁹Fe reactions were measured using a stacked foil activation technique combined with HPGe gamma-ray spectrometry up to the deuteron energy of 24 MeV. Measured data were critically compared with the available literature data and theoretical data extracted from the TENDL-2012 library, and found only partial agreements among them. Cross-sections of ^natCu(d,x)⁵⁹Fe reactions are reported here for the first time in the energy region of 19–23 MeV. Measured cross-sections of the long-lived ⁶⁵Zn, ^60gCo and ⁵⁹Fe radionuclides are significant for understanding the activation behaviour of copper, an essential structural material used in accelerator and nuclear industry.     

Excitation functions of neutrons induced reactions on terbium from threshold to 20 MeV

Cross-sections for (n,2n), (n,p), and (n,α) reactions have been measured on terbium isotopes at the neutron energies from 13.5 to 14.8 MeV using the activation technique in combination with high-resolution gamma-ray spectroscopy. Data are reported for the following reactions: ¹⁵⁹Tb(n,2n)^158m+gTb, ¹⁵⁹Tb(n,p)¹⁵⁹Gd, and ¹⁵⁹Tb(n,α)¹⁵⁶Eu. The cross sections were also estimated with the TALYS-1.4 nuclear model code, at neutron energies varying from the reaction threshold to 20 MeV. The results were discussed and compared with experimental data found in the literature, and with the comprehensive evaluation data in ENDF/B-VII.1 and JENDL-4.0 libraries.     

Activation cross section data of proton induced nuclear reactions on lanthanum in the 34–65 MeV energy range and application for production of medical radionuclides

Journal of Radioanalytical and Nuclear Chemistry - Activation cross sections of the natLa(p,x)139,137m,137g,135,134,133mCe, natLa(p,x)135,134,133La and 133m,133g,131Ba nuclear reactions have been...     

Mass–yield distributions of fission products from photo-fission of natPb induced by 50–70 MeV bremsstrahlung

The mass–yield distributions of various fission products have been determined in the 50-, 60- and 70-MeV end point bremsstrahlung induced fission of ^natPb using off-line γ-ray spectrometric technique in the electron linac at Pohang Accelerator Laboratory, Korea. The mass–yield distributions are symmetric with average mass of 102.34, 102.25 and 102.03 and FWHM of 21, 22 and 23 mass unit, respectively. From the present data and literature data in the 50–85 MeV bremsstrahlung induced fission of ²⁰⁹Bi the following observations were obtained: (i) The average masses of the yield distributions in the 50–85 MeV bremsstrahlung induced fission of ^natPb and ²⁰⁹Bi are around 102.25 ± 0.25 and 103 ± 0.5, respectively. (ii) The FWHM of the mass–yield distributions increases from about 21 mass units at 50 MeV to 23 mass units at 70–85 MeV, which is explained from the point of increase in multi-chance fission probability with increasing excitation energy. (iii) Within the bremsstrahlung energy range of 50–85 MeV, the role of nuclear structure effect in the mass–yield distribution was observed in the photo-fission of ²⁰⁹Bi, whereas it was not seen in case of ^natPb. This may be due to the presence of so many isotopes in ^natPb unlike mono-isotopic ²⁰⁹Bi.     

Measurement of excitation functions of the natAg(α,x) reactions up to 45 MeV

Journal of Radioanalytical and Nuclear Chemistry - We measured excitation functions for the production of the 108m,108g,109g,110m,110g,111gIn, the 109g,111mCd, and the 105g,106m,110m,111gAg in...     

Activation cross section measurements of 16O(n,t) above 18.1?MeV up to 33.1?MeV

We have measured the cross sections of the ¹⁶O(n,t) reactions above 18.1 up to 33.1 MeV in an neutron activation method. H₂O (water) as an ¹⁶O target was irradiated with semi-monoenergetic neutrons generated from the ⁹Be(p,n)⁹B reaction with 25–35 MeV protons. The neutron flux was obtained with the aid of previous study by Uwamino et al. (Nucl Instr Methods A 271:546, 1988). The tritium activities were measured by using the liquid scintillation counting (LSC) method. The present value for the cross section of ¹⁶O(n,t) reaction agrees with previous values measured by using the same LSC method at similar neutron energy ranging from 18.1 up to 33.1 MeV.     

Experimental measurements and theoretical calculations for proton,deuteron and α-particle induced nuclear reactions on calcium: special relevance to the production of <Superscript>43,44</Superscript>Sc

The cross sections of the proton, deuteron and α-particle induced nuclear reactions on Ca were determined experimentally up to 20 MeV. The obtained experimental data were validated theoretically using EMPIRE-3.2 and TALYS-1.6. The production yields of ⁴³Sc and ^44m,gSc radioisotopes were calculated and discussed in view of the reported experimental data. Of all the production routes, the ⁴⁴Ca(p,n)^44m,gSc and ⁴³Ca(d,n)^44m,gSc showed highest yields of 1206 MBq/µA.h (15 → 5 MeV) and 204 MBq/µA.h (8 → 0 MeV), respectively. The α-particles induced reactions on ^natCa or ⁴⁰Ca were found to be suitable for producing considerable activity of ⁴³Sc at energy range 8–20 MeV.     

The isomeric ratios in photonuclear reactions of natural strontium induced by bremsstrahlungs in the giant dipole resonance region and by 65 MeV bremsstrahlung

We have determined the isomeric ratio of ^85m,gSr in photonuclear reactions of natural strontium induced by bremsstrahlungs with end-point energies in the giant dipole resonance (GDR) region as well as the isomeric ratios of ^85m,gSr and ^84m,gRb produced at 65 MeV bremsstrahlung. In GDR region the target was irradiated at electron accelerator Microtron MT-25 of the Flerov Laboratory of Nuclear Reaction, Joint Institute for Nuclear Research, Dubna, Russia. The target irradiation with 65 MeV bremsstrahlung was performed at the linear electron accelerator of the Pohang Neutron Facility, Pohang, South Korea. The gamma spectra of the samples irradiated in both cases were measured with spectroscopic systems consisting of 8192 channel analyzer and high-energy resolution (180 keV at gamma ray 1332 keV of ⁶⁰Co) HP(Ge) semiconductor detector Canberra. The GENIE2000 (Canberra) computer program was used for data processing. The results were discussed and compared with those of other authors.     

Excitation functions of natPb(d,x) 206,205,204,203,202Bi, 203cum,202m,201cumPb and 202cum,201cumTl reactions up to 50 MeV

Cross-sections of deuteron induced nuclear reactions on lead were measured up to 50 MeV using the standard stacked foil irradiation technique and high resolution γ-ray spectrometry. Experimental cross-sections and derived integral yields are presented for the ^natPb(d,x) ^{206,205,204,203,202}Bi, ^{203cum,202m,201cum}Pb and ^{202cum,201cum}Tl reactions. The experimental data were compared with the results from literature and with the data in the TENDL-2013 library (obtained with TALYS code). The cross-section data were analyzed also with the theoretical results calculated by using the ALICE–IPPPE-D and EMPIRE-D codes.     

Cross section calculation of (n,p) and (n,2n) nuclear reactions on Zn,Mo and Pb isotopes with ~ 14 MeV neutrons

Journal of Radioanalytical and Nuclear Chemistry - In this article, we are presenting the results of model calculations for (n,p) and (n,2n) reaction cross sections using the standard nuclear...     

Cross-sections for formation of <Superscript>178m2</Superscript>Hf and <Superscript>179m2</Superscript>Hf through reactions on natural hafnium at neutron energy 14.8 ± 0.2 MeV

The cross sections for formation of metastable state of ¹⁷⁸Hf (^178m2Hf, 574.215 keV, 31 y) and ¹⁷⁹Hf (^179m2Hf, 362.55 keV, 25.05 d) through reactions induced by 14.8 ± 0.2 MeV neutrons on natural hafnium were measured for the first time. The monoenergetic neutron beam was produced via the ³H(d, n)⁴He reaction on ZF-300-II Intense Neutron Generator at Lanzhou University. Induced gamma activities were measured by a gamma-ray spectrometer with high-purity germanium (HPGe) detector. Measurements were corrected for gamma-ray attenuations, random coincidence (pile-up), dead time and fluctuation of neutron flux. The neutron fluence were determined by the cross section of ⁹³Nb(n, 2n)^92mNb reaction. The neutron energy in the measurement were by the cross section ratios of ⁹⁰Zr(n, 2n)^89m+gZr and ⁹³Nb(n, 2n)^92mNb reactions.     

Measurement of isomeric yield ratios for the natHo(γ,xn)164m,g;162m,gHo reactions in the bremsstrahlung energy region from 45 to 65 MeV

We have measured the isomeric yield ratios for the ^164m,gHo and the ^162m,gHo isomeric pairs formed via photonuclear reactions ¹⁶⁵Ho(γ,n)^164m,gHo and ¹⁶⁵Ho(γ,3n)^162m,gHo in the bremsstrahlung energy region from 45 to 65 MeV in steps of ?E = 5 MeV by the activation method. The induced γ-activities of the irradiated holmium foils were measured by a coaxial high-purity germanium detector coupled to a PC-based multichannel analyzer. In order to improve the accuracy of the experimental results the necessary corrections were made. The experimental results at bremsstrahlung energies of 45, 50, 55, 60, and 65 MeV are 0.408 ± 0.027, 0.413 ± 0.027, 0.427 ± 0.029, 0.452 ± 0.032, and 0.448 ± 0.031 for the ^164m,gHo isomeric pair, and 0.587 ± 0.041, 0.624 ± 0.044, 0.652 ± 0.045, 0.637 ± 0.045, and 0.668 ± 0.046 for the ^162m,gHo isomeric pair, respectively. The present results are the first measurements at bremsstrahlung energies just above the giant dipole resonance region. The obtained results confirm the dependence of isomeric ratios on the incident photon energy as observed in some earlier experiments.     

Adsorption isotherms of CO2, CO,N2, CH4, Ar and H2 on activated carbon and zeolite LiX up to 1.0 MPa

The adsorption isotherms of CO₂, CO, N₂, CH₄, Ar, and H₂ on activated carbon and zeolite LiX were measured using a volumetric method. Equilibrium experiments were conducted at 293, 308, and 323 K and pressures up to 1.0 MPa. The adsorption isotherm and heat of adsorption were analyzed for two pressure regions of experimental data: pressures up to 0.1 MPa and up to 1.0 MPa. Each experimental isotherm was correlated by the Langmuir, Sips, Toth and temperature dependent Sips isotherm models, and the deviation of each model was evaluated. The Sips and Toth models showed smaller deviation from the experimental data of adsorbents than the Langmuir model. Isosteric heats of adsorption were calculated by the temperature dependent Sips model and are presented along with surface loading. From deviation analysis, it is recommended that the isotherm in the proper pressure range be used to appropriately design adsorptive processes.