Incident Deuteron Research Articles

On the accuracy of cross-section measurements of neutron-induced reactions using the activation technique with natural targets: The case of Ge at E[formula omitted] MeV

Several cross-section measurements of neutron-induced reactions on Ge found in literature, are performed utilizing natGe targets. The production of the same residual nucleus as the measured one might occur as a result of the unavoidable presence of neighboring isotopes in the same target, acting as a contamination. Corrections must be made based on theoretical calculations and models in order to resolve this problem. The accuracy and limits of a methodology for these “theoretical corrections” are investigated in this work using isotopically enriched targets, which can produce very accurate results without the need for such corrections. Experimental cross-section measurements have been made for the 76Ge(n,2n)75Ge, 72Ge(n,α)69mZn and 72Ge(n,p)72Ga reactions, via the activation technique, with the 27Al(n,α)24Na reaction used as reference, employing both a natGe and isotopically enriched Ge targets. The 3H(d,n)4He (D–T) reaction was used for producing the quasi-monoenergetic neutron beam in the 5.5 MV Tandem Accelerator Laboratory of the National Centre for Scientific Research “Demokritos” in Athens, Greece, at an incident deuteron beam energy of 2.9 MeV. Using HPGe detectors, γ-ray spectroscopy was applied to determine the induced γ-ray activity of the residual nuclei.

Assessment of production of 66Ga via 66Zn(d,2n)66Ga reaction as a medical radioisotope using GEANT4, MCNPX and TALYS computer nuclear codes

66Ga due to its positron emitting and suitable half-life is a medical radioisotope that has been developed for positron emission tomography (PET) imaging. While there are several production routes for 66Ga, in this study, production of gallium-66 via the 66Zn(d,2n)66Ga reaction was predicted by GEANT4 and MCNPX nuclear codes. SRIM and TALYS codes are also used in the calculation process. The ranges of deuteron particles in the zinc target are calculated by SRIM and GEANT4 are reported to be 426.64 and 428.08 μm in 16 MeV, respectively. The cross-section values of the reaction estimated by GEANT4 toolkit and four microscopic models of the TALYS code are very close to experimental data. Moreover, the values of 66Ga thick target yields in the zinc target for the energy of 16 MeV of incident deuteron are obtained to be 364.97, 523.11, and 506.6 μCi/μAh by GEANT4, TALYS, and MCNP codes, respectively. The small discrepancy between simulated results and experimental data illustrates that the applied nuclear codes are desirable tools for predicting nuclear reactions in various routes.

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The ARRONAX cyclotron, acronym for “Accelerator for Research in Radiochemistry and Oncology at Nantes Atlantique” is a new facility installed in Nantes, France. A dedicated program has been launched on production of innovative radioisotopes for PET imaging and for β − and α targeted radiotherapy using protons or α particles. Since the accelerator is also able to deliver deuteron beams up to 35 MeV, we have reconsidered the possibility of using them to produce medical isotopes. Indeed, in some cases, the use of deuterons allows higher production yield than protons.186Re is a β − emitter which has chemical properties close to the widely used 99mTc and has been used in clinical trials for palliation of painful bone metastases resulting from prostate and breast cancer. 186Re production cross section has been measured between 9 and 23 MeV using the ARRONAX deuteron beam and the stacked-foil technique.A novelty in our work is the use of a monitor foil behind each natW target foil in order to record efficiently the deuteron incident flux and energies all over the stack relying on the International Atomic Energy Agency (IAEA) recommended cross section of the natTi(d,x)48V reaction. Since a good optimization process is supposed to find the best compromise between production yield and purity of the final product, isotope of interest and contaminants created during irradiation are measured using gamma spectrometry.Our new sets of data are presented and compared with the existing ones and with results given by the TALYS code calculations. The thick target yield (TTY) has been calculated after the fit of our experimental values and compared with the IAEA recommended ones.Presented values are in good agreement with existing data. The deuteron production route is clearly the best choice with a TTY of 7.8 MB/μAh at 30 MeV compared to 2.4 MBq/μAh for proton as projectile at the same energy. The TALYS code gives satisfactory results for 183,186Re isotopes.

A systematic analysis of deuteron breakup

Inclusive breakup cross sections for deuterons incident on a wide range of nuclei at different incident energies are studied. In our analysis, we use the post-form distorted-wave-Born approximation (DWBA) to calculate the elastic and nonelastic breakup cross sections. We also calculate exciton and statistical compound-nucleus model cross sections to account for pre-equilibrium and equilibrium emissions. The calculations are performed using the code EMPIRE and are compared to the available experimental data. The comparisons of the integrated cross sections reveal a generally good agreement between the calculations and the data. However, systematic discrepancies are observed between the calculated double differential neutron and proton cross sections and the data, especially for heavier targets. Possible reasons for the disagreements between the theoretical predictions and the experimental data are discussed.

Deuteron and α-particle-induced nuclear reactions on 45Sc: activation cross section measurement and thick target yield evaluation

Systematic measurements of nuclear reaction cross sections were done in the low energy range for the two reactions 45Sc(d,p)46Sc and 45Sc(α,n)48V. Thin foils of high-purity (99.95%) natural Sc targets (100% 45Sc), purchased from Good-Fellow, were irradiated with 10 and 20 MeV incident deuteron and α-particle energies, respectively, at beam current of 100 nA using MGC-20 cyclotron. For precise measurements, high-purity Ti and Cu foils were used for monitoring the actual deuteron and α-particle beam intensities, respectively. The conventional stacked-foil technique was applied for measurement and calculation of the cross section values using a high-resolution γ-ray spectrometer for measuring the radioactivity. Nuclear model code EMPIRE-3.2 was used for calculation of the investigated excitation functions. The obtained results were compared with the experimental values and TENDEL-2021 data which are based on TALYS-1.96 code calculations. The integrated yields for the two reactions, based on the proposed average excitation functions, were estimated.

DIGE differential cross-section data for 6Li and 19F analysis

In this work we report the absolute differential cross-sections for the 429, 478 and 656 keV gamma-rays emission from the nuclear reactions 6Li(d, nγ)7Be, 6Li(d, pγ)7Li and 19F(d, pγ)20F, respectively. The energies of the incident deuterons were varied from 790 to 1995 keV in steps of 30 and 50 keV. The target was a thin natLiF layer evaporated onto a self-supporting Ag film. The gamma-rays were detected using an HPGe detector placed at an angle of 90° with respect to the beam direction. The obtained cross-sections were compared with the existing data in literature. The validity of measured cross-sections was checked through a thick target benchmarking procedure. All sources of the uncertainties in the measurements were deduced and reported.

Investigation of (d, 3n) reaction cross section using theoretical nuclear codes calculations on some nuclear materials

It is important to examine the effects of the nuclear reaction, which is used as a building material in nuclear reactors. Nuclear reactions occur as a result of the interaction between incident particles with the target nuclei. The charged particle-induced reactions have prime importance in understanding the reaction mechanism which can be applicable to understand the particles resulting from the reaction. It is useful to develop shielding the particle accelerators and fusion reactors. The present study contributes to providing the theoretical prediction of excitation functions for 112Cd (d, 3n)111In, 141Pr (d, 3n)140Nd, 167Er (d, 3n)166Tm, 197Au (d, 3n)196Hg and 209Bi (d, 3n)208Po reactions using theoretical model codes such as TALYS-1.95, EMPIRE-3.2.3, and ALICE-2014 within the incident deuteron energy range of threshold energy to 50 MeV. Also, newly developed (d, 3n) cross-section formula (Kavun, 2020) calculations have been performed for these reactions at 20 MeV of deuteron energy. Lastly, all calculated results have been compared with one another and with the previously published experimental data of the EXFOR database.

Probing yields and angular distributions of Be(d,n) neutrons with novel target of compressed beryllium-powder

A comprehensive study was conducted in the Cyclotron laboratory at National Research Tomsk Polytechnic University on the use of a new type of target utilized in the production of fast-neutrons. The flux and spectra of the fast-neutrons emitted by a novel target of compressed beryllium powder were studied. The neutron angular distribution was measured using Fe and Al foils as detectors in different angular situations of the target relative to the incident deuteron beam. It was found that there are some discrepancies in the neutron flux at 0° degree for the detectors, up to about 20% for different target-beam angle. Likewise, the flux of neutrons in the energy range between 1 and 6 MeV make up about 83% of the total flux. Compering with previous works using solid target, we found an increase of nearly twice the yield of fast neutrons. And there is a probability that increase would rise steadily as the deuteron energies exceed 12 MeV as was the case in our work. The results of this study are new and promising and we can obtain a relatively greater neutron yield when using a compressed powder target. This is reflected positively on many applications that use fast-neutron beams, such as radiotherapy, radioactive isotopes, and even nuclear fusion experiments, among others.

Three-body force effect on Deuteron–Deuteron elastic scattering at medium energies

In the framework of Glauber optical limit approximation taking into account D-state of deuteron and including three-nucleon force effect, the deuteron–deuteron elastic scattering differential cross-section is calculated at momenta [Formula: see text] [Formula: see text] [Formula: see text],GeV/c for incident deuteron. The D-state effect is not enough to obtain an agreement with the experimental data. The inclusion of three-nucleon force is necessary to improve the agreement with the data at momentum transferred squared greater than [Formula: see text] (GeV/c)2.

Three-body optical potentials in (d,p) reactions and their influence on indirect study of stellar nucleosynthesis

Model uncertainties arising due to suppression of target excitations in the description of deuteron scattering and resulting in a modification of the two-body interactions in a three-body system are investigated for several $(d,p)$ reactions serving as indirect tools for studying the astrophysical $(p,\ensuremath{\gamma})$ reactions relevant to $rp$ process. The three-body nature of the deuteron-target potential is treated within the adiabatic distorted-wave approximation (ADWA) which relies on a dominant contribution from the components of the three-body deuteron-target wave function with small $n\text{\ensuremath{-}}p$ separations. This results in a simple prescription for treating the explicit energy dependence of two-body optical potentials in a three-body system requiring nucleon optical potentials to be evaluated at a shifted energy with respect to the standard value of half the deuteron incident energy. In addition, the ADWA allows for leading-order multiple-scattering effects to be estimated, which leads to a simple renormalization of the adiabatic potential's imaginary part by a factor of two. These effects are assessed using both nonlocal and local optical potential systematics for $^{26}\mathrm{Al}$, $^{30}\mathrm{P}$, $^{34}\mathrm{Cl}$, and $^{56}\mathrm{Ni}$ targets at a deuteron incident energy of 12 MeV, which is typical for experiments with radioactive beams in inverse kinematics. The model uncertainties induced by the three-body nature of deuteron-target scattering are found to be within $40%$ both in the main peak of angular distributions and in total $(d,p)$ cross sections. At higher deuteron energies, around 60 MeV, model uncertainties can reach 100% in the total cross sections. A few examples of application to astrophysically interesting proton resonances in $^{27}\mathrm{Si}$ and $^{57}\mathrm{Cu}$ obtained using $(d,p)$ reactions and mirror symmetry are given.

Measurements of neutron energy spectra of 9Be(d,n)10B reaction with a thick beryllium target * *Supported by the National Natural Science Foundation of China (11875155, 11705071, 12075105), the NSFC-Nuclear Technology Innovation Joint Fund (U1867213), the NSAF (U1830102), the Fundamental Research Funds for the Central Universities of China (lzujbky-2020-kb09) and the Project of National Defense Science and Technology Industry for Nuclear Power

Novel measurements of the neutron energy spectra of the 9Be(d,n)10B reaction with a thick beryllium target are performed using a fast neutron time-of-flight (TOF) spectrometer for the neutron emission angles and , and the incident deuteron energies are 250 and 300 keV, respectively. The neutron contributions from the 9Be(d,n)10B reaction are distributed relatively independently for the ground state and the first, second, and third excited states of 10B. The branching ratios of the 9Be(d,n)10B reaction for the different excited states of 10B are obtained for the neutron emission angles and , and the incident deuteron energies are 250 and 300 keV, respectively. The branching ratio of the 9Be(d,n)10B reaction for the third excited state decreases with increase in the incident deuteron energy, and the branching ratios for the ground state and the second excited state increase with increase in the neutron emission angle.

Measurement of double-differential thick-target neutron yields of the C(d,n) reaction at 12, 20, and 30 MeV

ABSTRACT While designing deuteron accelerator neutron sources for radioisotope production, nuclear data for light elements such as Li, Be, and C have been systematically measured in the deuteron energy range from a few MeV to around 50 MeV. Currently, the experimental data available on double-differential thick-target neutron yields (DDTTNYs) are insufficient, especially for deuteron energies between 18 and 33 MeV. In this study, we measured the DDTTNYs of (d,n) reactions on natC target for incident deuteron energies of 12, 20, and 30 MeV using the multiple-foil activation method to improve nuclear data insufficiency. The neutrons were detected at emission angles of 0°, 10°, 20°, 30°, and 45°. We applied the GRAVEL code for the unfolding process to derive the DDTTNYs. The results were compared with the calculation by the deuteron-induced reaction analysis code system (DEURACS), and the DEURACS calculation underestimated our results 12 and 20 MeV deuteron. The present data were also used to confirm the systematics of the differential neutron yields at 0° and total neutron yield per incident deuteron in 12–30 MeV of deuteron energy.

DIGE differential cross section data for oxygen isotopic analysis

In this work the absolute differential cross sections of the 18O(d,pγ)19O (Eγ = 1376 keV) ,18O(d,nγ)19F (Eγ = 1357 keV) and 16O(d,pγ)17O (Eγ = 871 keV) reactions were measured for the isotopic analysis of oxygen by DIGE technique. The energy of the incident deuterons was varied from 590 to 1994 keV in steps of 10 keV. Gamma-rays and backscattered deuterons were collected simultaneously by an HPGe detector at an angle of 90° and an ion implanted Si detector at a scattering angle of 165° with respect to the beam direction. An anodic Ta216,18O5 thin layer on tantalum was used throughout the cross sections measurement. The validity of obtained cross sections was checked by benchmarking experiment with a thick Y2O3 target. The overall systematic uncertainty of the measured cross section data was estimated to be better than 9%.

Neutron-induced activation cross-sections for fusion technology applications

Activation method was employed to measure the cross section for the 58Ni(n,pα)54Mn and 63Cu(n,pα)59Fe reactions in the energy range from the threshold up to 21 MeV. The quasi-monoenergetic neutrons in the energy range from 14 to 21 MeV were produced via the 3H(d,n)4He reaction at 1, 2, 3 and 4 MeV incident deuteron energies. High purity Ni and Cu samples with natural isotopic composition and dimensions of ϕ12x5 mm and ϕ20x5 mm respectively were utilized. The gamma-ray spectrometry using HPGe detector was utilized to measure the activity induced in the sample. The cross sections were determined relative to the standard cross section the 27Al(n,α)24Na reaction. The results for the 63Cu(n,pα)59Fe reaction cross section were obtained for the first time.

Effects of an induced three-body force in the incident channel of ( d,p ) reactions

A widely accepted practice for treating deuteron breakup in $A(d,p)B$ reactions relies on solving a three-body $A+n+p$ Schr\"odinger equation with pairwise $A$-$n$, $A$-$p$ and $n$-$p$ interactions. However, it was shown in [Phys. Rev. C \textbf{89}, 024605 (2014)] that projection of the many-body $A+2$ wave function into the three-body $A+n+p$ channel results in a complicated three-body operator that cannot be reduced to a sum of pairwise potentials. It contains explicit contributions from terms that include interactions between the neutron and proton via excitation of the target $A$. Such terms are normally neglected. We estimate the first order contribution of these induced three-body terms and show that applying the adiabatic approximation to solving the $A+n+p$ model results in a simple modification of the two-body nucleon optical potentials. We illustrate the role of these terms for the case of $^{40}$Ca($d,p$)$^{41}$Ca transfer reactions at incident deuteron energies of 11.8, 20 and 56 MeV, using several parameterisations of nonlocal optical potentials.

Performance evaluation of an energy tuning assembly for neutron spectral shaping

An energy tuning assembly (ETA) was designed to be fielded at the National Ignition Facility (NIF) to modify the characteristic D-T fusion spectrum to include a prompt fission neutron spectral component. The ETA was characterized at the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory to measure the shaped spectrum from an incident deuteron breakup neutron source, test the proposed neutron spectroscopy techniques used to inform the flux measurements at NIF, and validate the ability to predict ETA performance using a Monte Carlo Neutral Particle (MCNP) simulation. Activation foils (i.e., Ni, In, Au, Al) were exposed to a collimated 33-MeV deuteron-breakup beam originating from a tantalum breakup target. The source spectrum absent the ETA was characterized using a set of activation foils and the STAYSL unfolding code. Finally, the ETA-modified spectrum was obtained using activation foil unfolding with a χ2ν=0.92. The ETA-modified unfolded spectrum agreed with the MCNP-simulated prediction in the energy range of 0.1–14 MeV, but exhibited disagreements in the 10 eV–100 keV region. This work demonstrates shaping of the NIF neutron spectrum via the ETA to be a viable path forward for tailored neutron beams at NIF.

Estimation of the Fast-Ion Anisotropy Effect on the Neutron Source Intensity Measurement and the Experimental Observation

In the large helical device (LHD) deuterium plasma experiment, the neutron emission rate and the shot-integrated neutron yield are measured with the neutron flux monitor (NFM) and the neutron activation system (NAS), respectively, where the neutron emission is assumed to be isotropic in the plasma. The differential cross section of the D(d,n) 3 He reaction has a large anisotropy for the forward direction of the incident deuteron direction. LHD has intensive tangential neutral beam injectors (NBIs), which may cause an anisotropic neutron emission in the plasma. The angular distribution of the neutron emission is calculated from the fast-ion distribution function evaluated by a code that solves Fokker-Plank equations for the 180-keV tangential NBI. The effect of the anisotropic neutron emission on the NFM and NAS measurements is estimated by a general-purpose Monte Carlo N-particle (MCNP) code calculations. Also, the effect is confirmed experimentally. The neutron emission rate measured with the NFM near the equatorial port is about 10% larger than that with the NFM at the top of the LHD center axis. The shot-integrated neutron yield measured with NAS is 25% larger than that with NFM at the top of the LHD center axis in the case of the tangential neutral beam injection, which is consistent with the MCNP calculation.

Role of breakup processes in deuteron-induced spallation reactions at 100–200 MeV/nucleon

Use of deuteron-induced spallation reactions at intermediate energies has recently been proposed for transmutation of several long-lived fission products (LLFPs). In the design study of a transmutation system using a deuteron primary beam, accurate cross section data of deuteron-induced reactions on the LLFPs are indispensable. Reliable model predictions play an important role in completing the necessary cross section data since currently available experimental data are very limited. Under the circumstances, we have been developing a code system dedicated for deuteron-induced reactions, which is called DEURACS. Aiming to predict the production cross sections of residual nuclei, the purpose of the present work is to clarify a role of deuteron breakup processes in deuteron-induced spallation reactions at intermediate energies. Isotopic production cross sections of residual nuclei in the deuteron-induced reactions on 93Zr and 107Pd at 100-200 MeV/nucleon are analyzed using DEURACS, in which the breakup processes are explicitly taken into account. The calculated cross sections are decomposed into individual components corresponding to the absorption of either neutron or proton in the incident deuteron, or the deuteron itself. The calculated cross sections reproduced the experimental data well over a wide mass number range of residual nuclei. From a component-by-component analysis, it was found that the components of nucleon absorption have the significant contributions to the production of residual nuclei. Consideration of the breakup processes is essential to predict the production cross sections of residual nuclei in deuteron-induced reactions. The framework of DEURACS is applicable to deuteron-induced spallation reactions at intermediate energies.

Consistent account of deuteron-induced reactions on natCr up to 60 MeV

Purpose: Accurate new measurements of low-energy deuteron-induced reaction cross sections for natural Cr target can enhance the related database and the opportunity for an unitary and consistent account of the involved reaction mechanisms. Methods: The activation cross sections of $^{51,52,54}$Mn, $^{51}$Cr, and $^{48}$V nuclei for deuterons incident on natural Cr at energies up to 20 MeV, were measured by the stacked-foil technique and high resolution gamma spectrometry using U-120M cyclotron of the Center of Accelerators and Nuclear Analytical Methods (CANAM) of the Nuclear Physics Institute of the Czech Academy of Sciences (NPI CAS). They as well as formerly available data for deuteron interactions with Cr isotopes up to 60 MeV are the object of an extended analysis of all processes from elastic scattering until the evaporation from fully equilibrated compound system, but with a particular attention given to the BU and DR mechanisms. Results: The new measured activation excitation functions proved essential for the enrichment of the deuteron database, while the theoretical analysis of all available data strengthens for the first time their consistent account provided that (i) a suitable BU and DR assessment is completed by (ii) the assumption of PE and CN contributions corrected for decrease of the total-reaction cross section due to the leakage of the initial deuteron flux towards BU and DR processes. Conclusions: The suitable description of nuclear mechanisms involved within deuteron-induced reactions on chromium, taking into account especially the BU and DR direct processes, is validated by an overall agreement of the calculated and measured cross sections including particularly the new experimental data at low energies.

Measurement of deuteron induced gamma-ray emission cross sections on nitrogen for analytical applications

Deuteron induced gamma-ray emission cross-section values from the 14N(d,pγ4-1)15N (Eγ = 1885 keV), 14N(d,pγ6-1)15N (Eγ = 2297 keV), 14N(d,pγ5-0)15N (Eγ = 7299 keV) and 14N(d,pγ7-0)15N (Eγ = 8310 keV) nuclear reactions were measured in the 600–2000 keV range of the incident deuteron energies, in 30 keV steps at the laboratory angle of 90°, utilizing a thin C3H6N6 target evaporated onto a self-supporting Ag film. The thick target gamma-ray yields were measured in the same experimental setup using a thick TiN target. These measurements were conducted using the deuteron beam of the 3 MV Van de Graaff electrostatic accelerator of Nuclear Science and Technology Research Institute (NSTRI) in Tehran. The obtained results were compared with the previously reported data. The validity of the measured differential cross sections was verified through a thick target benchmarking experiment. The overall systematic uncertainty of the measured values was estimated and reported.