Activation Cross Sections Research Articles

Activation cross-sections of proton induced reactions on natHf in the 38–65 MeV energy range: Production of 172Lu and of 169Yb

In the frame of a systematical study of light ion induced nuclear reactions on hafnium, activation cross sections for proton induced reactions were investigated. Excitation functions were measured in the 38 to 65 MeV energy range for the $^{nat}$Hf(p,xn)$^{180g,177,176,175,173}$Ta, $^{nat}$Hf(p,x)$^{180m,179m,175,173,172,171}$Hf, $^{177g,173,172,171,170,169}$Lu and $^{nat}$Hf(p,x)$^{169}$Yb reactions by using the activation method, combining stacked foil irradiation and off line gamma ray spectroscopy. The experimental results are compared with earlier results in the overlapping energy range, and with the theoretical predictions of the ALICE IPPE and EMPIRE theoretical codes and of the TALYS code reported in the TENDL2015 and TENDL2017 libraries. The production routes of $^{172}$Lu (and its parent $^{172}$Hf) and of $^{169Y}$b are reviewed.

Proton-induced activation cross section measurement for aluminum with proton energy range from 0.4 to 3 GeV at J-PARC

ABSTRACT We have started an experimental program to measure activation cross sections systematically in the proton-induced spallation reaction in structural materials commonly used in high-intensity proton accelerator-based facilities, such as Japan Proton Accelerator Research Complex (J-PARC). As the first step of the program, aluminum (Al) was chosen to verify the adequacy of the measurement technique implemented in a J-PARC proton beam environment because data of Al have been relatively well studied both by experimental measurement and simulation. Activation cross sections of 7Be, 22Na, and 24Na in Al were measured at proton energy points from 0.4, 1.3, 2.2 to 3.0 GeV, which could be delivered smoothly from the synchrotron. The validity of experimental data has been verified by introducing an effective proton numbers determination procedure. We compared the measured data with existing experimental data, the evaluated data (JENDL-HE/2007), and the calculations with several intra-nuclear cascade models by the Particle and Heavy Ion Transport code System (PHITS) code. Although the experimental data agreed with JENDL-HE/2007, the calculations underestimated about 40%. This could come from the evaporation model (generalized evaporation model) being implemented in the PHITS code. We found that the calculations agreed with the experimental data by an upgraded PHITS code.

Activation cross sections of alpha-induced reactions on nat In for 117m Sn production

Abstract The production of 117mSn by charged-particle induced reactions is an interesting topic for medical application. Production cross sections of α-induced reactions on natIn for 117mSn up to 50 MeV were measured using the stacked foil technique and activation method. The integral yield of 117mSn was estimated using the measured cross sections. The results were compared with experimental data investigated earlier and theoretical calculation. Measured cross sections for 113Sn and 116m,117,118mSb isotopes were also presented.

Production cross sections of deuteron-induced reactions on natural palladium for Ag isotopes

Abstract Activation cross sections for deuteron-induced reactions on natural palladium were measured up to 24 MeV using the stacked-foil method and the high resolution gamma-ray spectroscopy. The production cross sections of 103Ag, the parent of a medical radioactive isotope 103Pd, were obtained. We found that our result is in good agreement with the previous data up to 20.3 MeV, and obtained new data at higher energies. In addition, the production cross sections of 104g+mAg, 105Ag, 106mAg, 110mAg and 111Ag were presented.

Activation cross section and isomeric cross section ratio for the 76Ge(n,2n)75m,gGe process

.We measured neutron-induced reaction cross sections for the 76Ge(n,2n)75m,gGe reactions and their isomeric cross section ratios sigma_{m}/sigma_{g} at three neutron energies between 13 and 15MeV by an activation and off-line gamma-ray spectrometric technique using the K-400 Neutron Generator at the Chinese Academy of Engineering Physics (CAEP). Ge samples and Nb monitor foils were activated together to determine the reaction cross section and the incident neutron flux. The monoenergetic neutron beams were formed via the 3H(d,n)4He reaction. The pure cross section of the ground state was derived from the absolute cross section of the metastable state and the residual nuclear decay analysis. The cross sections were also calculated using the nuclear model code TALYS-1.8 with different level density options at neutron energies varying from the reaction threshold to 20MeV. Results are discussed and compared with the corresponding literature data.

Activation cross sections for the 110Pd(n,2n) reaction and the isomeric cross-sections ratio of 109m,gPd in the neutron energy range of 13–15 MeV

The 110Pd(n,2n)109m,gPd reaction cross-sections and the isomeric cross section ratios (σm/σg) in the neutron energy range of 13-15 MeV have been measured by an activation and off-line g-ray spectrometric technique using the 300Pd Neutron Generator at the Chinese Academy of Engineering Physics (CAEP). The natural Pd samples and Nb monitor foils were activated together to determine the reaction cross section and the incident neutron flux. The neutron beams were generated via the 3H(d,n)4He reaction. The pure cross section of the ground-state was derived from the absolute cross section of the metastable state and the residual nuclear decay analysis. The 110Pd(n,2n)109m,gPd reaction excitation functions and their isomeric cross section ratios were also calculated theoretically using the computer code TALYS-1.8 with different level density options. Results are discussed and compared with the corresponding literature data.

Activation cross section and isomeric cross-section ratio for the 151Eu(n,2n)150m,gEu process

The cross sections of 151Eu(n,2n)150m,gEu reactions and their isomeric cross section ratios σm/σt have been measured experimentally. Cross sections are measured, relative to a reference 93Nb(n,2n)92mNb reaction cross section, by means of the activation technique at three neutron energies 13.5, 14.1, and 14.8 MeV. Monoenergetic neutron beams were formed via the 3H(d,n)4He reaction and both Eu2O3 samples and Nb monitor foils were activated together to determine the reaction cross section and the incident neutron flux. The activities induced in the reaction products were measured using high−resolution gamma ray spectroscopy. Cross sections were also evaluated theoretically using the numerical nuclear model code, TALYS-1.8 with different level density options at neutron energies varying from the reaction threshold to 20 MeV. Results are discussed and compared with the corresponding literature.

Measurement of activation cross sections of alpha particle induced reactions on iridium up to an energy of 50 MeV

Cross sections of alpha particle induced nuclear reactions on iridium were investigated using a 51.2-MeV alpha particle beam. The standard stacked-foil target technique and the activation method were applied. The activity of the reaction products was assessed without chemical separation using high resolution gamma-ray spectrometry. Excitation functions for production of gold, platinum and iridium isotopes (196m2Au, 196m,gAu, 195m,gAu, 194Au, 193 m,gAu, 192Au, 191m,gAu, 191Pt, 195mPt, 194gIr, 194mIr, 192gIr, 190gIr and 189Ir) were determined and compared with available earlier measured experimental data and results of theoretical calculations using TALYS code system. Cross section data were reported for the first time for the natIr(α,x)196m2Au, natIr(α,x)196m,gAu, natIr(α,x)191Pt, natIr(α,x)195mPt, natIr(α,x)194gIr, natIr(α,x)194mIr, natIr(α,x)190gIr and natIr(α,x)189Ir processes. A possible production route for 195mPt, the potentially important radionuclide in nuclear medicine, is discussed.

Study of activation cross sections of deuteron induced reactions on erbium in the 32–50 MeV energy range

Activation cross sections of the natEr(d,x)163,165,166,167,168,170Tm and natEr(d,x)171,161Er nuclear reactions have been measured in the 32–50MeV energy range, above 40MeV for the first time. The activation method with stacked foil irradiation technique and gamma-ray spectroscopy were used. The experimental cross sections were compared with the theoretical predictions in the TENDL-2015 library.

Study of activation cross sections of deuteron induced reactions on barium. Production of 131Cs, 133Ba

Abstract In the frame of a systematic study of deuteron induced activation processes on middle mass elements, excitation functions of the nat Ba(d,x) 135,133,132 La, 135m,133m,133mg,131mg Ba, 136mg,134mg,132,129 Cs reactions were measured up to 50 MeV for the first time. Cross sections were measured with the activation method using a stacked foil irradiation technique followed by HPGe γ -ray spectrometry. A comparison with the results of the nuclear model TALYS code (reported in the TENDL-2015 library) was done. The potential use of the deuteron induced reactions on Ba for applications ( 131 Cs and 131 Ba production) is discussed.

Towards an activation cross section measurement of the 17O(p,γ)18F reaction in a wide energy range

The CNO cycles are fusion processes in stars that convert hydrogen to helium. These hydrogen burning processes occur in several sites and stages of stellar evolution, such as red giants, asymptotic giant branch (AGB) stars, massive stars, and classical novae.One of the important reactions in the CNO-III and CNO-IV cycles is 17O(p,γ)18F [1]. The only available total cross section measurement in a wide energy range for this reaction dates back to several decades ago [2] which makes the theoretical extrapolation to astrophysical energies more difficult and introduces uncertainty.The aim of the present work is to provide precise total cross section data in the energy range between about 500 keV and the 2MeV using the activation method. The experimental campaign at the new tandetron accelerator of Atomki is in progress.

Bismuth activation with quasi-Maxwellian neutrons at kT∼30keV

Bismuth capture of neutrons is the termination point of the $s$-process cycle of nucleosynthesis in stellar environments. A new measurement is reported here for neutron activation of bismuth with an intense quasi-Maxwellian neutron source at $kT\ensuremath{\sim}30\phantom{\rule{0.16em}{0ex}}\mathrm{keV}$. The measurement was performed at the SARAF phase I accelerator facility by bombarding a 1.5-mA proton beam on the liquid-lithium larget. The cross section of the $^{209}\mathrm{Bi}(n,\ensuremath{\gamma})$ capture reaction leading to the $^{210}\mathrm{Bi}$ ground state was determined by combining $\ensuremath{\beta}$ measurements from the $^{210\mathrm{g}}\mathrm{Bi}$ decay and $\ensuremath{\alpha}$ and $\ensuremath{\gamma}$ from the subsequent $^{210}\mathrm{Po}$ decay, along with detailed Monte Carlo simulations of the $^{7}\mathrm{Li}(p,n)$ reaction kinematics and the activation experimental setup. Deduced Maxwellian averaged cross sections (MACS) for $^{209}\mathrm{Bi}(n,\ensuremath{\gamma})^{210\mathrm{g}}\mathrm{Bi}$ at $kT=30\phantom{\rule{0.16em}{0ex}}\mathrm{keV}$ using the ENDF, JEFF, and JENDL databases for the corrections and extrapolations yielded a value of $1.84\ifmmode\pm\else\textpm\fi{}0.09\phantom{\rule{0.16em}{0ex}}\mathrm{mb}$. A comparison is made with previous measurements, including time-of-flight (TOF) measurements of the total bismuth capture cross section. Plans for obtaining the MACS for capture to the bismuth-210 metastable state in the reaction $^{209}\mathrm{Bi}(n,\ensuremath{\gamma})^{210\mathrm{m}}\mathrm{Bi}$ are discussed, along with estimates based on our results in comparison with TOF measurements. The bismuth neutron activation cross section is also of importance for design of GenIV reactor coolant and subcritical accelerator driven systems, especially in light of the 3 million year half-life of the $^{210\mathrm{m}}\mathrm{Bi}$ isomer.

Activation cross section and isomeric cross section ratios for the ( n,2n ) reaction on Eu153

The $^{153}\mathrm{Eu}(n,2n)^{152}\mathrm{Eu}^{\mathrm{m}1,\mathrm{m}2,g}$ cross section was measured by means of the activation technique at three neutron energies in the range 13--15 MeV. The quasimonoenergetic neutron beam was formed via the $^{3}\mathrm{H}(d,n)^{4}\mathrm{He}$ reaction, in the Pd-300 Neutron Generator at the Chinese Academy of Engineering Physics (CAEP). The activities induced in the reaction products were measured using high-resolution \ensuremath{\gamma}-ray spectroscopy. The cross section of the population of the second high-spin (${8}^{\ensuremath{-}}$) isomeric state was measured along with the reaction cross section populating both the ground (${3}^{\ensuremath{-}}$) and the first isomeric state (${0}^{\ensuremath{-}}$). Cross sections were also evaluated theoretically using the numerical code TALYS-1.8, with different level density options at neutron energies varying from the reaction threshold to 20 MeV. Results are discussed and compared with the corresponding literature.

Improving Activation Cross Sections for Fusion Applications

High-quality nuclear data are required for reliable design calculations of fusion reactors as well as analyses related to safety, licensing, waste management, and decommissioning issues. The current work is focused on improving neutron activation cross-section data for nuclear reactions needed for fusion applications but also satisfying specific astrophysical needs. The cross-section data were evaluated on the basis of nuclear model calculation using the TALYS-1.8 code with varying nuclear model parameters. The evaluated data were compared to recent experimental data taken from EXFOR and other evaluated nuclear data libraries. Validation of the current evaluations has been performed using both differential and integral data sets. The updated cross-section data are going to be adopted into the new version of the TALYS Evaluated Nuclear Data Library.

Activation cross sections of proton induced nuclear reactions on neodymium up to 65 MeV

In the frame of a systematic study of the activation cross sections of charged particle induced nuclear reactions on rare earths for production of therapeutic radionuclides, proton induced reactions on neodymium were measured up to 65 MeV energy, above 45 MeV for the first time. The excitation functions of the natNd(p,x)150,149,148m,148g,146,144,143,141Pm, 149,147,141,140,139m,138Nd, 142,138mPr and 139gCe nuclear reactions were assessed by using stacked foil activation technique and high resolution gamma-spectrometry. The excitation functions were compared to the theoretical predictions, available in the TENDL-2015 library based on latest version of the TALYS code. The application of the data for medical isotope production is shortly discussed.

Investigation of activation cross sections of proton induced reactions on rhodium up to 70 MeV for practical applications

Excitation functions were measured for production of the $^{113,111,110}$Sn, $^{115m,114m,113m,112m,111g,110g}$In and $^{111m,109}$Cd radioisotopes by bombardment of In targets with proton beams up to 70 MeV, some of them for the first time. The new results are compared with the earlier experimental data and with the theoretical data in the TENDL-2014 (Talys1.6 based) library. Thick target yields were deduced and application of the new data for production of medically relevant $^{110m}$In, $^{111g}$In, $^{113m}$In and $^{114m}$In, as well as applicability for thin layer activation (TLA) are discussed.

Measurement of activation cross sections for quasi-monoenergetic neutron induced reactions of 89Y

The neutron induced cross sections of the 89Y(n,2n)88Y, 89Y(n,3n)87Y and 89Y(n,4n)86Y reactions were measured in the neutron energy range of 15.2 to 37.2 MeV by using an activation and off-line $\gamma$ -ray spectrometric technique. The quasi-monoenergetic neutrons used for the above reactions are based on a 9Be(p,n) reaction. Simulations of the neutron spectra from the Be target were done using the MCNPX 2.6.0 program. Theoretical calculations were performed for the 89Y(n,2n)88Y, 89Y(n,3n)87Y and 89Y(n,4n)86Y reaction cross sections using nuclear model code Talys 1.8. The measured and calculated cross sections were compared with the literature data given in EXFOR and the TENDL-2015 data libraries. The present data of the 89Y(n,xn) reaction were also compared with the similar data of the 89Y( $\gamma$ ,xn) reaction to examine the effect of the entrance channel parameters as well as the role of projectiles and ejectiles.

Activation Cross Section and Isomeric Cross-Section Ratio for the (n,2n) Reaction on 113,115In

Cross sections of the 113In(n,2n)112m,gIn and 115In(n,2n)114m,gIn reactions and their isomeric cross-section ratios σm/σg have been measured by means of the activation technique at three neutron energies in the range 13 to 15 MeV. Indium samples and niobium monitor foils were activated together to determine the reaction cross section and the incident neutron flux. The monoenergetic neutron beam was produced via the 3H(d,n)4He reaction at the Pd-300 Neutron Generator of the Chinese Academy of Engineering Physics. The activities induced in the reaction products were measured using high-resolution gamma-ray spectroscopy. The pure cross section of the ground state was derived from the absolute cross section of the metastable state and the residual nuclear decay analysis. Cross sections were also evaluated theoretically using the numerical nuclear model code TALYS-1.8 with different level density options at neutron energies varying from the reaction threshold to 20 MeV. Results are discussed and compared with the corresponding literature.

Thick and Thin Target 7Li(p,n)7Be Neutron Spectra Below the Three-Body Breakup Reaction Threshold

Recently, we measured the 70Zn(n,γ)71Znm activation cross sections using the 7Li(p,n)7Be neutron source for 2.0 MeV < Ep < 3.7 MeV. Since the time-of-flight and multiple foil activation techniques cannot be applied due to the continuous beam structure and weak neutron flux at the facility, we have to rely on calculated neutron energy spectra for data reduction procedure. There are existing Monte Carlo–based codes such as Protons In Neutrons Out (PINO) and SimLiT for calculation of 7Li(p,n)7Be neutron source spectra at these energies. However, these two codes predicted different neutron spectra at these energy regions. We therefore decided to study the thick and thin target 7Li(p,n)7Be neutron spectra from the reaction threshold to the three-body breakup threshold by deterministic calculation. The predicted neutron spectra near threshold were validated by experimental neutron spectra. Our neutron spectra were compared with those predicted by PINO and SimLiT. Our neutron spectra at Ep = 2.8 and 3.5 MeV agree perfectly with those predicted by SimLiT but not with those predicted by PINO.

Investigation of activation cross sections for deuteron induced reactions on strontium up to 50 MeV

Excitation functions were measured for the natSr(d,x)88,87m,87g,86g,85gY, 87m,85g,83g,82Sr, 86g,84g,83,82m,81gRb reactions by the stacked foil activation technique and high-resolution gamma-spectrometry up to 50MeV. We present the first experimental activation cross section data for all investigated reactions. Our experimental data are compared with the TALYS code results as available in the TENDL-2015 on-line library. Use of deuteron induced reactions on Sr for production of medical isotopes is discussed.