Proton-induced Reactions Research Articles

Experimental investigation on nuclear reactions using a laser-accelerated proton and deuteron beam

We report an experimental investigation on nuclear reactions using an intense, ultra-short laser-accelerated proton and deuteron beam generated by the interaction of 25 fs, 150 TW Ti: sapphire laser pulse with normal thin foils and foils containing deuterium atoms. The production of a positron-emitting short-lived 11C radio-isotope from the interaction of protons and deuterium ions with a solid boron palette by means of 11B (p, n)11C and 10B (d, n)11C nuclear reactions was studied. The maximum radioactivity in the optimized laser irradiation condition was found to be 5.2 kBq per laser shot, which corresponds to ∼9 × 106 atoms of 11C isotopes using the 11B (p, n)11C reaction. The relative efficiency of 11C production using a proton and deuteron beam was also explored experimentally. About 30 % enhancement in 11C activity was observed with CD2 coated targets. It was also found that because of the relatively low deuteron energy threshold of the reaction 10B (d, n)11C, even the low energy part of the accelerated deuterons in the spectrum can be used for efficient 11C production. In the same setup, the proton-induced fusion reaction in the boron target (p + 5B11 ⇒ 3α + 8.7 MeV) was also studied. The resultant fusion yield and alpha particle energy spectrum was measured.

Measurement of deuteron-induced nuclear reactions cross-sections on 197Au and on natCu focused on the theranostic 197m,gHg

Theranostic 197m,gHg of high specific activity may be produced by proton or deuteron activation of gold. The particle choice affects the isomeric ratio. In order to compare both projectiles, we re-measured cross-sections of the nuclear reactions 197Au(d,x)197mHg, 197gHg, 198mAu, 198gAu, 196m2Au, 196m1+gAu in the energy range of 8.3–19.7 MeV having employed usual stacked-foil method. The obtained values were compared with previously measured data and with prediction of the TALYS nuclear reaction model code adopted from the TENDL-2017 library. Experimental data were used for calculation of the thick target yields. The yields for the isomeric pair 197m,gHg were confronted with those for recently re-measured proton-induced reactions. We also provide a new data set for the reaction natCu(d,x)63Zn.

Proton-induced reactions on molybdenum

Cross sections for 34 proton-induced nuclear reactions on isotopically enriched molybdenum ($^{92,94\ensuremath{-}98,100}\mathrm{Mo}$) leading to production of $^{92}\mathrm{Tc}$, $^{93\mathrm{m}}\mathrm{Tc}$, $^{93\mathrm{g}}\mathrm{Tc}$, $^{94\mathrm{m}}\mathrm{Tc}$, $^{94\mathrm{g}}\mathrm{Tc}$, $^{95\mathrm{m}}\mathrm{Tc}$, $^{95\mathrm{g}}\mathrm{Tc}$, $^{96\mathrm{m}+\mathrm{g}}\mathrm{Tc}$, $^{97\mathrm{m}}\mathrm{Tc}$, $^{99\mathrm{m}}\mathrm{Tc}$, $^{101}\mathrm{Tc}$, $^{91(\mathrm{m}+\mathrm{g})}\mathrm{Mo}$, $^{93\mathrm{m}}\mathrm{Mo}$, $^{99}\mathrm{Mo}$, $^{89\mathrm{m}}\mathrm{Nb}$, $^{89\mathrm{g}}\mathrm{Nb}$, $^{91\mathrm{m}}\mathrm{Nb}$, $^{92\mathrm{m}}\mathrm{Nb}$, $^{95\mathrm{m}}\mathrm{Nb}$, $^{95\mathrm{g}}\mathrm{Nb}$, $^{96}\mathrm{Nb}$, and $^{97\mathrm{m}+\mathrm{g}}\mathrm{Nb}$ were measured in the energy range 8--19 MeV with the activation method using individual irradiations. The experimental data were compared with published data from natural abundance and isotopically enriched targets as well as with the predictions of the nuclear reaction code talys. Special attention was given to the medically relevant $^{100}\mathrm{Mo}$($p,2n$)$^{99m}\mathrm{Tc}$ and $^{100}\mathrm{Mo}$($p,pn$)$^{99}\mathrm{Mo}$ as well as nine reaction cross sections that had not previously been measured in this energy range.

Measurement of cross-sections of proton-induced nuclear reactions on 197Au focused on the production of the theranostic pair 197m,gHg

We measured cross-sections of the nuclear reactions 197Au(p,x)197mHg, 197gHg, 195mHg, 195gHg, 196m2Au, 196m1+gAu, 194m+gAu in the energy range of 6.4–35.3 MeV having used stacked-foil technique with high purity gold foils. The results were compared with previously published data and with prediction of the TALYS nuclear reaction model code adopted from the TENDL-2017 library. Thick target yields were deduced from the measured data. Production of the theranostic isomeric pair 197m,gHg is thoroughly discussed.

Fragment production in proton–induced reaction on Bi209 target at intermediate energy range

We used the phasotron of the Laboratory of Nuclear Problems at JINR to irradiate isotopically pure $^{209}\mathrm{Bi}$ target with 660 MeV protons. Cross sections of the fragment production with mass numbers $24\ensuremath{\le}A\ensuremath{\le}210$ u were measured for the first time using the direct $\ensuremath{\gamma}$-spectrometry method with a high-resolution HpGe detector. The $\ensuremath{\gamma}$ lines of the fragments have been identified, and the cross sections determined by the deimos code. The results of the measured nuclide cross section have been parametrized in terms of a three-parameter equation in order to reproduce the real isobaric distribution. Fission and spallation mass yields have been reconstructed on the base of charge distribution of reaction products. The main reaction results have been compared with other experimental data obtained from the proton-induced reaction at 600 MeV as well as with theoretical model calculations using the crisp code.

Excitation functions and yield measurements for Proton Induced Reactions in Stainless Steel: Special relevance to Proton Activation Analysis

In this work, the excitation functions for protons induced nuclear reactions with stainless steel's constituent elements were measured and the results were used in Proton Activation Analysis (PAA) of 18/10 steel samples which was carried out at Egyptian MGC-20 cyclotron. The elemental concentrations were also checked using the EDX technique. The reactions natFe(p,x)56Co, natNi(p,α)55Co and natCr(p,x)52gMn were studied from threshold up to 14.3 MeV proton energy. TALYS-1.6 and EMPIRE-3.2.2 codes were used to model the excitation functions of the investigated reactions. For quantitative analysis using PAA, the apparent reaction yields (i.e. not corrected for the γ-ray attenuation), were measured for each reaction along the proton energy range as well as the target thickness, and normalization factors were given.

Microscopic description of proton-induced spallation reactions with the constrained molecular dynamics (CoMD) model

We studied the complete dynamics of the proton-induced spallation process with the microscopic framework of the constrained molecular dynamics (CoMD) model. We performed calculations of proton-induced spallation reactions on 181Ta, 208Pb, and 238U targets with the CoMD model and compared the results with a standard two-step approach based on an intranuclear cascade model followed by a statistical deexcitation model. The calculations were also compared with recent experimental data from the literature. Our calculations showed agreement with some aspects of the experimental data and suggest further improvements in the models. We point out that this CoMD study represents the first complete dynamical description of spallation reactions with a microscopic N-body approach and may lead to advancements in the physics-based modeling of the spallation process.

Measurement of cross sections for proton-induced reactions on natural Zn

We present the cross sections for the natZn(p,x)67Cu and natZn(p,x)67Ga reactions within a proton energy range of 47.5–99.2 MeV. We efficiently separated the overlapping gamma-ray spectra of the two isotopes 67Cu and 67Ga, using an analytical method without radiochemical separation. The present data were compared with previous data from the literature, typically obtained by radiochemical separation before measuring the gamma-ray spectra of the two isotopes. Our results for the two isotopes generally showed greater or smaller values than those reported in the literature, except for some data concerning partial energy ranges, which were in agreement with the literature data. The present data were also compared with the TENDL-2017 library based on the TALYS code.

Probing nuclear bubble configurations by proton-induced reactions

In the framework of the isospin-dependent Boltzmann-Uehling-Uhlenbeck transport model, nuclear bubble configuration in the hypothetical $^{48}$Si nucleus is studied by proton induced central reaction at an incident beam energy of 0.8 GeV/nucleon. It is found that along the beam direction more energetic protons are emitted with bubble configuration in the target. In the forward angles, compared with the case without bubble configuration, less scattered energetic protons are emitted with bubble configuration in the target. We thus provide a new way to probe the bubble configuration in nuclei.

Vortex Target: A New Design for a Powder-in-Gas Target for Large-Scale Radionuclide Production

This paper presents a design and working principle for a combined powder-in-gas target. The excellent surface-to-volume ratio of micrometer-sized powder particles injected into a forced carrier-gas-driven environment provides optimal beam power-induced heat relief. Finely dispersed powders can be controlled by a combined pump-driven inward-spiraling gas flow and a fan structure in the center. Known proton-induced nuclear reactions on isotopically enriched materials such as 68Zn and 100Mo were taken into account to be conceptually remodeled as a powder-in-gas target assembly, which was compared to thick target designs. The small irradiation chambers that were modeled in our studies for powdery ‘thick’ targets with a mass thickness (g/cm2) comparable to 68Zn and 100Mo resulted in the need to load 2.5 and 12.6 grams of the isotopically enriched target material, respectively, into a convective 7-bar pressured helium cooling circuit for irradiation, with ion currents and entrance energies of 0.8 (13 MeV) and 2 mA (20 MeV), respectively. Current densities of ~2 μA/mm2 (20 MeV), induces power loads of up to 4 kW/cm2. Moreover, the design work showed that this powder-in-gas target concept could potentially be applied to other radionuclide production routes that involve powdery starting materials. Although the modeling work showed good convective heat relief expectations for micrometer-sized powder, more detailed mathematical investigation on the powder-in-gas target restrictions, electrostatic behavior, and erosion effects during irradiation are required for developing a real prototype assembly.

Nuclear radii from nuclear masses

Single uncharged pion production in neutron- and proton-induced reactions on complex nuclei, combined with the nuclear Fermi Gas Model, has been used to evaluate the average equivalent radius of a [Formula: see text] nucleus directly from the experimental nuclear mass-values of [Formula: see text] and its neighbors [Formula: see text] and [Formula: see text] isobars. A simple formula without adjustable parameters has been derived which gives nuclear radius-values that are in good agreement with updated, equivalent root-mean-square (rms) radius-values derived from experiments for a set of 540 nuclides comprising spherical, quasi-spherical, stable and long-term half-life nuclides. We shall call by RFNM-approach the present method of nuclear radius determination.

Systematic study of proton-induced spallation reactions with the Constrained Molecular Dynamics (CoMD) model

Proton – induced spallation reactions on 238U, 208Pb, 181Ta and 197Au targets at high energies were studied and investigated using the microscopic Contrained Molecular Dynamics (CoMD) model. Total fission cross sections, the ratio fission cross section to residue cross section, mean kinetic energy of fission fragments, mass yield curves and the number of nucleons emitted, before and after scission, as well as the total nucleon multiplicity were calculated using the CoMD model and compared with experimental data from the literature. Some of our calculations showed satisfactory agreement with available experimental data.The calculations of cross sections and the ratio fission cross section to residue cross section as a function of the proton energy gave us the opportunity to estimate observables for unmeasured nuclides.

Systematic study of proton-induced spallation reactions with microscopic and phenomenological models

Proton induced spallation reactions on 238U, 208Pb, 181Ta and 197Au targets at high energies were investigated using the microscopic Contrained Molecular Dynamics (CoMD) model and the phenomenological models INC and SMM. We have calculated the total fission cross sections, the ratio fission cross section to residue cross section, the mass yield curves and the excitation energy after the intranuclear cascade using the CoMD model and the INC/SMM phenomenological models. We made a comparison between the models and the experimental data from the liter- ature. Our calculations showed satisfactory agreement with available experimental data and suggest further improvements in the models. Our study with the CoMD code represents the first complete dynamical description of the spallation process with a microscopic code based on an effective nucleon-nucleon interaction.

Calculation of reactions cross section for proton-induced nuclear reactions on Iodine-127 isotope

Radioisotope production for nuclear medicine is tomography devices. Both single photon emissions computed tomography (SPECT) and positron emission tomography (PET) is used for diagnosis in nuclear medicine we have calculated the reaction cross section and investigated the excitation functions for the formation of 127,126 125 I , 126,127,128 Xe , 126,125 Te isotopes in the interactions of proton particle with the nucleus of the iodine-127 isotope. The analysis shows that there is a variation of interaction cross-section with a variation of energy of the incident particle. The result shows that the plots of the 127 I (p,ng), and 127 I (p,2ng), graphs have full excitation curve. The productions confirm the presence of Xenon-127 and Xenon-126 isotopes are possible at the energy range of 0 to 30 MeV from the iodine-127 nucleus. Keywords : Cross-Section; Excitation function; Nuclear Reaction; Radioisotope; Statistical Multistep Reaction

Measurement of Differential Cross Section for Proton-induced Deuteron Breakup at 108 MeV

The experiment was performed at CCB IFJ PAN in Krakow with the use of the BINA detector. The experimental program and data analysis of proton-induced deuteron breakup reaction at 108 MeV are presented.

Reexamination of Proton-induced Reactions on $^{\rm nat}$Mo at 19--26 MeV and Study of Target Yield of Resultant Radionuclides

Reexamination of Proton-induced Reactions on $^{\rm nat}$Mo at 19--26 MeV and Study of Target Yield of Resultant Radionuclides

Production of Th229 for medical applications: Excitation functions of low-energy protons on Th232 targets

As a part of a general program to evaluate production routes for $^{229}\mathrm{Th}$, we studied production of $^{229}\mathrm{Th}$ via proton-induced reactions on $^{232}\mathrm{Th}$ targets bombarded with low-energy protons, ${E}_{\mathrm{p}}\ensuremath{\le}40\phantom{\rule{0.16em}{0ex}}\mathrm{MeV}$. The reported excitation functions include those for proton-induced reactions on natural thorium yielding to $^{228,229,230&232}\mathrm{Pa}$ isotopes; $^{232}\mathrm{Th}$(p,xn) reactions, where $x=1$, 3, 4, and 5, at proton energy ranges of 12--40 MeV. Although the data for $^{232}\mathrm{Th}(p,n)^{228}\mathrm{Pa}$, $^{232}\mathrm{Th}(p,3n)^{230}\mathrm{Pa}$, and $^{232}\mathrm{Th}(p,5n)^{232}\mathrm{Pa}$ reactions were deduced by direct analysis of the thorium foils after irradiation, the data for $^{232}\mathrm{Th}(p,4n)^{229}\mathrm{Pa}$ were obtained by radiochemical techniques. The half-life of $^{229}\mathrm{Pa}$ was evaluated and determined to be 1.55 \ifmmode\pm\else\textpm\fi{} 0.01 d. Further, the \ensuremath{\alpha}-branching ratio, \ensuremath{\alpha}/(\ensuremath{\alpha} + EC) of $^{229}\mathrm{Pa}$ was evaluated to be 0.53 \ifmmode\pm\else\textpm\fi{} 0.10% by allowing $^{229}\mathrm{Pa}$ to decay for $\ensuremath{\sim}7\phantom{\rule{0.16em}{0ex}}\mathrm{d}$, then chemically extracting and quantifying the $^{225}\mathrm{Ac}$ (${t}_{1/2}=10.0\ifmmode\pm\else\textpm\fi{}0.1\phantom{\rule{0.16em}{0ex}}\mathrm{d}$) from $^{229}\mathrm{Pa}$ samples. In addition, we report the effective production cross section of $^{229}\mathrm{Th}$ in a thick $^{232}\mathrm{Th}$ target in the proton energy range of 23--33 MeV. The peak of the excitation function for the $^{232}\mathrm{Th}(p,4n)^{229}\mathrm{Pa}$ reaction occurs at 162 \ifmmode\pm\else\textpm\fi{} 14 mb and ${E}_{p}=29.7\ifmmode\pm\else\textpm\fi{}0.5\phantom{\rule{0.16em}{0ex}}\mathrm{MeV}$. This is only slightly larger than the effective cross section for the $^{232}\mathrm{Th}(p,x)^{229}\mathrm{Th}$ reaction (obtained from a thick target experiment). This data indicates that the $^{232}\mathrm{Th}(p,4n)^{229}\mathrm{Pa}$ reaction is the major reaction pathway for the cumulative $^{232}\mathrm{Th}(p,x)^{229}\mathrm{Th}$ reaction cross section in this energy range. The measured cross sections were compared with theoretical cross sections using the simulation codes Particle and Heavy Ion Transport code System (PHITS) and Monte Carlo Neutral Particle 6 (MCNP6). At proton energy ranges of 12--33 MeV, the cumulative excitation function predicted by PHITS for the reactions leading to $^{229}\mathrm{Th}$ was in close agreement with the experimental function, whereas the function predicted by MCNP6 was a factor of two higher at the peak of the excitation function.

Excitation functions of proton-induced reactions on natFe and natZr targets for the production of cobalt and niobium isotopes

Excitation functions of proton-induced reactions for the natural iron and zirconium targets were measured from their respective threshold energies to 22 and 20 MeV. The conventional stacked foil technique was used in combination with the off-line $\gamma$ -ray spectroscopy at the BARC-TIFR Pelletron facility, Mumbai. The computer code SRIM 2013 was used to calculate the energy degradation along the stack and the proton beam intensity was measured via the natCu(p,x)62Zn monitor reaction. The measured excitation functions were then compared with the literature data available in EXFOR database as well as with the theoretical values from the TALYS-1.8 code and the TENDL-2017 data library. The shapes of the excitation function for all the reactions were reproduced well by TALYS-1.8. In terms of absolute values, for some reactions the data are in good agreement with both the literature data and TALYS-1.8 whereas, for others there is a slight deviation either from the literature data or from the theoretical values of TALYS-1.8 and TENDL-2017.

Investigation of 3He Emission Spectra in Proton Induced Reactions for Some Elements Used in Fusion Reactor Structural Materials

Reaksiyon tesir kesiti bir nükleer reaksiyonun gerçekleşme ihtimalini ifade eder. Hızlandırıcılar, güç santralleri, fisyon ve füzyon reaktörleri gibi nükleer tesislerde güvenliğin sağlanabilmesi için kullanılan malzeme ile parçacıklar arasındaki gerçekleşebilecek tüm etkileşimlerin göz önüne alınması gerekmektedir. Tesir kesiti verileri; radyoizotop üretimi, zırhlama ve malzeme geliştirme çalışmaları olmak üzere geniş bir alanda kullanılmaktadır. Bu yüzden, bir reaksiyonun tesir kesiti verilerinin ve reaksiyon sonucu açığa çıkan parçacıkların enerji spektrumlarının deneysel ve teorik yöntemlerle araştırılması gerekmektedir. Bu çalışmada, tek enerjili protonlarla bombardıman edilen füzyon reaktörü yapısal elementleri 27Al, 56Fe, 58Ni ve 90Zr için, 3He enerji spektrumları teorik modeller ile incelenmiştir. Elde edilen sonuçlar deneysel verilerle karşılaştırılarak analiz edilmiştir.

Quantification of lithium at ppm level in geological samples using nuclear reaction analysis

Proton-induced reaction (p,α) is one type of nuclear reaction analysis (NRA) suitable especially for light element quantification. In the case of lithium quantification presented in this work, accelerated protons with an energy about of 850 keV were used to induce the 7Li(p,α)4He reaction in standard reference and geological samples such as tourmaline and other Li-minerals. It is shown that this technique for lithium quantification allowed for measurement of concentrations down below one ppm. The possibility to relate the lithium content with the boron content in a single analysis was also demonstrated using tourmaline samples, both in absolute concentration and in lateral distribution. In addition, Particle induced X-ray emission (PIXE) was utilized as a complementary IBA technique for simultaneous mapping of elements heavier than sodium.