Étude du dosage de Ti, V, Cr, Fe, Ni, Cu et Zn par activation avec des protons d'énergie limitée a 20 MeV

Ion beam activation of natCu, natTi, natNi and measurement of product formation cross sections at low energy (<10 MeV)

In this study we investigated the production cross sections of natCu(p, x)63,65Zn, natTi(p, x)48V, natNi(p, x)55Co,61Cu and natCu(α, x)66,67,68Ga, natTi(α, x)49,51Cr, natNi(α, x)63,65Zn reactions in the low energy range using the foil activation technique. The samples were activated in vacuum at 5 MV tandem (Pelletron) accelerator installed at National Centre for Physics (NCP), Islamabad, Pakistan. The reaction products were identified with the help of off-line gamma ray spectroscopy system connected with Genie 2000 software. The data analysis revealed the production of different radioisotopes that have valuable importance in monitoring charged-particle beams and medical applications. The measured results were verified by comparing them with earlier evaluated data as well as with the theoretical values given in the TENDL-library based on TALYS-1.9 code calculations.

An overview of activation cross-section measurements of some neutron and charged-particle induced reactions in Bangladesh

Over the last several decades, our research group has been working on nuclear data measurements using a J-25 Neutron Generator, a TRIGA Mark II Research Reactor and a Tandem Accelerator at Savar, as well as an Am/Be neutron source at Rajshahi. The spectrum of fast neutrons having energies from 0.5 to 20 MeV in the core of the TRIGA reactor as well as from 1.5 to 11 MeV of the Am/Be source was well characterized for validation of evaluated data of neutron threshold reactions. Spectrum-averaged cross sections were determined by integral measurements. The integral values measured at both the reactor and the Am/Be source were compared with the integrated data deduced from measured and evaluated excitation functions of some nuclear reactions given in some data libraries. As example, the details on the integral and integrated cross sections of the 64Zn(n,p)64Cu and 60Ni(n,p)60Co reactions are discussed. In both cases, integral test shows that further improvement of the evaluated excitation function reported in data libraries is needed. The use of a newly developed facility at the 3 MV Tandem Accelerator in measurement of proton induced reaction cross sections in the energy region below 5 MeV is outlined, and new results on the 64Ni(p,n)64Cu and natNi(p,x)61Cu processes below 3 MeV are discussed.

Production, Purification, and Applications of a Potential Theranostic Pair: Cobalt-55 and Cobalt-58m

The emerging success of [⁶⁸Ga/¹⁷⁷Lu]Ga/Lu-DOTATATE as a theranostic pair has spurred interest in other isotopes as potential theranostic combinations. Here, we review cobalt-55 and cobalt-58m as a potential theranostic pair. Radionuclidically pure cobalt-55 and cobalt-58m have been produced on small cyclotrons with high molar activity. In vitro, DOTATOC labeled with cobalt has shown greater affinity for SSTR2 than DOTATOC labeled with gallium and yttrium. Similarly, [^58mCo]Co-DOTATATE has shown improved cell-killing capabilities as compared to DOTATATE labeled with either indium-111 or lutetium-177. Finally, PET imaging with an isotope such as cobalt-55 allows for image acquisition at much later timepoints than gallium, allowing for an increased degree of biological clearance of non-bound radiotracer. We discuss the accelerator targetry and radiochemistry used to produce cobalt-55,58m, emphasizing the implications of these techniques to downstream radiotracers being developed for imaging and therapy.

Excitation functions of proton induced reactions on titanium and copper

Excitation functions of the Tnati(p,x)S43,47c, V48 and Cnatu(p,x)⁶⁴Cu, Z62,65n reactions were measured in the energy range of 8.8-18.4 MeV by using the stacked-foil activation technique and off-line gamma spectroscopy. The irradiation was carried out at the superconducting linac of the Institute of Modern Physics, Chinese Academy of Sciences. Besides, the reliability and effectiveness of theoretical data from the TALYS code, recommended data of the International Atomic Energy Agency (IAEA) and evaluated nuclear data of the ENDF/B-VIII.0, JENDL-4.0/HE and PADF-2007 libraries were evaluated and verified by comparing with experimental data. Our experimental results agree with most of the available literature data. TALYS-1.95 code could not reproduce, in most cases, the experimental data. Evaluated nuclear data from the ENDF/B-VIII.0, JENDL-4.0/HE and PADF-2007 libraries are able to reproduce, in most cases, the experimental data trend. Recommended data of the IAEA are in good consistent with our work and most of the available literature data.

Nuclear model analysis of the 65Cu(α, n)68Ga reaction for the production of 68Ga up to 40 MeV

The charge particle (α) induced reactions on enriched copper (⁶⁵Cu) are investigated for the production of ⁶⁸Ga. The data sets of experimental cross sections are compiled, normalized and nuclear model analysis is done using calculational codes namely, ALICE-IPPE, TALYS 1.95 and EMPIRE 3.2. The theoretical production cross sections via alpha particle induced reactions are calculated to present a set of recommended cross sections. The calculated cross sections are utilized to deduce thick target yield (TTY) for the ⁶⁵Cu (α, n) ⁶⁸Ga reaction. The range of energy for production of ⁶⁸Ga is suggested up to 40 MeV having least contribution of radio-impurities.

Experimental investigation and theoretical evaluation of proton induced nuclear reactions on nickel

The cross-sections for proton-induced nuclear reactions on natural nickel were experimentally measured for the ^natNi(p,x)^60,61,64Cu, ^natNi(p,x)^55,57,58Co and ^natNi(p,x)⁵⁷Ni reactions from their respective thresholds up to 17 MeV proton energy. The stacked-foil technique in combination with HPGe γ-ray spectroscopy was used. Three codes were used in the theoretical calculations namely ALICE-IPPE, EMPIRE-3.2.2 and TENDL-2017. Comparison of the present results with the earlier reported experimental data and with the code results were carried out.

Excitation functions of proton induced nuclear reactions on natFe up to 16 MeV, with emphasis on radiochemical determination of low cross sections

Excitation functions for the formation of the radionuclides

Cross-sections for (p,x) reactions on natural chromium for the production of (52,52m,54)Mn radioisotopes

The production of positron-emitting isotopes of manganese is potentially important for developing contrast agents for dual-modality positron emission tomography and magnetic resonance (PET/MR) imaging, as well as for in vivo imaging of the biodistribution and toxicity of manganese. The decay properties of (52)Mn make it an excellent candidate for these applications, and it can easily be produced by bombardment of a chromium target with protons or deuterons from a low-energy biomedical cyclotron. Several parameters that are essential to this mode of production—target thickness, beam energy, beam current, and bombardment time—depend heavily on the availability of reliable, reproducible cross-section data. This work contributes to the routine production of (52g)Mn for biomedical research by contributing experimental cross-sections for natural chromium ((nat)Cr) targets for the (nat)Cr(p,x)(52g)Mn reaction, as well as for the production of the radiocontaminants (52m,54)Mn.

Activation cross-sections of proton induced reactions on natural Ni up to 65MeV

Production cross-sections of the (nat)Ni(p,x)(60,61)Cu, (56,57)Ni, (55,56,57,58)Co nuclear reactions were measured in five experiments up to 65MeV by using a stacked foil activation technique. The results were compared with the available literature values, predictions of the nuclear reaction model codes ALICE-IPPE, TALYS-1.4, and extracted data from the TENDL-2012 library. Spline fits were made on the basis of selected data, from which physical yields were calculated and compared with the literature values. The applicability of the (nat)Ni(p,x)(57)Ni, (57)Co reactions for thin layer activation (TLA) was investigated. The production rate for (55)Co was compared for proton and deuteron induced reactions on Ni.

Cross-section measurements for the formation of manganese-52 and its isolation with a non-hazardous eluent

With respect to the production of no-carrieradded 52Mn nuclear reactions on natural chromium were investigated. Cross sections of the reactions natCr(p, x)48V, 48,49,51Cr, 52g,mMn were determined in the proton energy range of 7.6 to 45MeV. Additionally, production yields of 52g,mMn and 51Cr were measured in the energy range from 8.2 to 16.9MeV and therefrom the calculated saturation thick target yields were obtained as (2.55±0.31), (6.96±0.57), and (1.53±0.15) GBq/μA, respectively. For in vivo applications like PET, low toxicity is critical and sufficient activity of a radiolabelled compound mandatory. Thus, additional purification steps after separation of radionuclides and target materials have to be avoided. However, no isolation procedure has been reported in the literature so far where radiomanganese is directly obtained in a nonhazardous solution. Therefore a new separation procedure was developed utilizing the cation-exchange resin DOWEX 50W×8 (H+-form). 52gMn was quantitatively isolated from “bulk” chromium after 3 to 4 h in non-hazardous 0.067M ammonium citrate solution. Up to 99% of 52gMn activity was harvested within 10 to 15 mL eluent solution with no measureable 51Cr impurities.

Theoretical calculations of the reaction cross-sections for proton-induced reactions on natural copper using ALICE-IPPE code

A theoretical study of the nuclear-reaction cross sections for proton-induced reactions on (63)Cu and (65)Cu was performed in the proton energy range from threshold values up to 50MeV. The produced nuclei were different isotopes of Zn, Cu, Ni, Co and Mn, some of which have important applications. The reaction cross-section calculations were performed using the ALICE-IPPE code, which depends on the pre-equilibrium compound nucleus model. This code is suitable for the studied energy and isotopic mass ranges. Approximately 14 excitation functions for the different reactions have been constructed from the calculated cross-section values. The excitation function curves for the proton reactions with natural copper targets have been constructed from those for enriched targets using the natural abundance of the copper isotopes. Comparisons between the calculated excitation functions with those previously experimentally measured are given whenever the experimental values were available. Some statistical parameters were introduced to control the quality of the fitting between both the experimental and the theoretical calculated cross-section values.

Activation cross-section measurements of some proton induced reactions on Ni, Co and Mo for proton activation analysis (PAA) purposes

The experimental proton induced reaction cross sections on some elements of the Havar alloy were measured using the activation method and the well established stacked-foil technique combined with high resolution gamma-ray spectroscopy. They included the reactions natNi(p,x)57Ni, natCo(p,x)58(m+g)Co and natMo(p,x)94g,95g,96(m+g)Tc, the aim being to obtain reliable data in the proton energy range up to 26 MeV for some important reactions to be used in the proton activation analysis of steel or other alloys. Irradiations were performed using the CS-30 Cyclotron at KFSH and RC, Riyadh, Saudi Arabia. The activity measurements were carried out in PNU laboratories, Riyadh, Saudi Arabia. The experimental excitation functions for the investigated reactions were constructed and compared with the performed computed theoretical nuclear model calculations using two different codes: ALICE-IPPE and TALYS. A comparison between our measured cross-section values and the available published data is also presented, with a view to checking the consistency of the reported experimental work from various laboratories.

Investigation of 50Cr(d,n)51Mn and natCr(p,x)51Mn processes with respect to the production of the positron emitter 51Mn

The positron emitter 51Mn (t1/2 = 46.2 min, Iβ+ = 97%) is of potential interest in positron emission tomography (PET). With a view to optimizing its production route, excitation functions for deuteron induced nuclear reactions on isotopically enriched (~95%) 50Cr were determined radiochemically over the energy range of 3 to 13 MeV and for proton induced nuclear reactions on natCr in the range of 18 to 38 MeV. Cross sections are presented for the reactions: 50Cr(d,2n) 50mMn, 50Cr(d,n) 51Mn, 50Cr(d,t)49Cr, 50Cr(d,p)51Cr, 50Cr(d,a)48V, 52Cr(d,2p)52V, natCr(p,x) 51Mn, natCr(p,x)52Mn, natCr(p,x)52mMn, natCr(p,x)54Mn, natCr(p,x)48Cr, natCr(p,x)49Cr, natCr(p,x) 51Cr, natCr(p,x)48V and natCr(p,x)45Ti. In the case of proton induced reactions on natCr, the isomeric cross section ratio for the isomeric pair 52m,gMn was also determined. The results are interpreted in terms of the spins of the two isomers concerned. Theoretical thick target yields were derived from the corresponding excitation functions. The maximum achievable thick target yield of 51Mn is 1.1 GBq/μAh in the case of the 50Cr(d,n) 51Mn reaction at Ed = 14 → 3 MeV, and 3.2 GBq/μAh in the case of the natCr(p,x)51Mn process for Ep = 40 → 20 MeV. The 50Cr(d,n) 51Mn process is the favourable production route for 51Mn, since the radioisotopic purity is high and a small-sized medical cyclotron is adequate to produce this positron emitter in sufficient quantities.

Experimental study of excitation functions of some proton induced reactions on natTi for beam monitoring purposes

Excitation functions of proton induced reactions on natTi, leading to the formation of 43,44m,44g,47Sc and 48V, were measured using the stacked-foil technique over the proton energies starting from the respective reaction threshold up to 27.5 MeV. The new experimental values were compared with earlier reported data. In general good agreement was found. Also in the case of 48V the results were compared with the cross-section values recommended by the International Atomic Energy Agency. A good agreement was observed.

Excitation functions of proton induced nuclear reactions on natural copper using a medium-sized cyclotron

Activation techniques have been used to measure the excitation functions of proton induced nuclear reactions on natural copper from their thresholds up to 27.5 MeV. The beam current was measured using a Faraday cup with secondary electron suppression, and the radioactivity of the products was determined via high-resolution gamma ray spectrometry. The data were compared with the data recommended by the IAEA wherever it was possible. A comparison of the new excitation functions with the theoretical calculations reported in the literature was undertaken to check the order of agreement between them. Good agreement was found for the results of 63Zn while the theoretical calculations overestimate the cross sections for 61Cu and 62Zn. The excitation function for the reaction natCu(p, x) 61Co was measured for the first time during this work. The integral yields of the radionuclides 62,63,65Zn, 61Cu and 61Co were calculated. 63Zn and 65Zn are produced over the whole energy range of 3 to 27.5 MeV and the yield gets saturated above 20 MeV. 62Zn, 61Cu and 61Co are produced at relatively high energies and have integral yield values between those of 63Zn and 65Zn. The relatively high yield of 62Zn is useful for the production of 62Zn/62Cu generator system.

Excitation functions of proton-induced reactions on natFe and enriched 57Fe with particular reference to the production of 57Co

Excitation functions of the reactions (nat)Fe(p,xn)(55,56,57,58)Co, (nat)Fe(p,x)(51)Cr, (nat)Fe(p,x)(54)Mn, (57)Fe(p,n)(57)Co and (57)Fe(p,alpha)(54)Mn were measured from their respective thresholds up to 18.5MeV, with particular emphasis on data for the production of the radionuclide (57)Co (T(1/2)=271.8d). The conventional stacked-foil technique was used, and the samples for irradiation were prepared by an electroplating or sedimentation process. The measured excitation curves were compared with the data available in the literature as well as with results of nuclear model calculations. From the experimental data, the theoretical yields of the investigated radionuclides were calculated as a function of the proton energy. Over the energy range E(p)=15-->5MeV the calculated yield of (57)Co from the (57)Fe(p,n)(57)Co process amounts to 1.2MBq/microAh and from the (nat)Fe(p,xn)(57)Co reaction to 0.025MBq/microAh. The radionuclidic impurity levels are discussed. Use of highly enriched (57)Fe as target material would lead to formation of high-purity (57)Co.

Excitation function measurements and integral yields estimation for natZnp,x reactions at low energies

Excitation functions have been measured for a number of proton-induced nuclear reactions on natural zinc in the energy range from 27.5 MeV down to their threshold energy, using the activation method on stacked foils. Excitation functions and thick target yield for the reactions leading to the formation of (67)Ga,(66)Ga,(68)Ga,(62)Zn and (65)Zn are presented and compared with earlier reported experimental data. The experimental cross-sections and the production yields are tabulated; the excitation functions and the thick target yield curves are plotted in graphs.

Excitation functions of (p,x) reactions on natural nickel between proton energies of 2.7 and 27.5MeV

Excitation functions have been measured for a number of proton induced nuclear reactions on natural nickel in the energy range from 27.5 MeV down to their threshold energy, using the activation method on stacked foils. Excitation functions for the reactions leading to the formation of (60)Cu, (61)Cu, (56)Ni, (57)Ni, (55)Co, (56)Co, (57)Co and (58)Co are presented and compared with earlier reported experimental data. Comparison with the recommended data reported by the International Atomic Energy Agency [Gul et al., 2001. Charged particle cross section database for medical radioisotope production. IAEA-TECDOC-1211, IAEA Vienna, Austria] is also presented when possible.

Comments on the feasibility of 61Cu production by proton irradiation of (nat)Zn on a medical cyclotron

Feasibility of 61Cu production in high radionuclidic purity form via (nat)Zn(p,x) 61Cu nuclear process is discussed. Based on the experimentally available cross-sections of the (nat)Zn(p,x) 61Cu, (nat)Zn(p,x) 60Cu and (nat)Zn(p,x) 64Cu nuclear processes the usefulness of the (nat)Zn(p,x) 61Cu process for high-scale production is questionable in the 22 --> 12 MeV energy range.

An overview of copper radionuclides and production of 61Cu by proton irradiation of (nat)Zn at a medical cyclotron

In this article, production methods and applications of copper radionuclides are overviewed with special attention toward (61)Cu, due to its interesting nuclear properties. Selection of production parameters for (61)Cu including: appropriate nuclear reaction, proton beam energy, target thickness and targetry method are discussed for NRCAM 30MeV medical cyclotron. (64)Zn(p,alpha)(61)Cu was selected as the best reaction and (61)Cu was produced by 22MeV proton bombardment of a 80 microm thick natural zinc target. After 180microAh irradiation, the resultant activity of (61)Cu was 6.006Ci (12.015mCi/microAh). The chemical separation method was easy, quick and efficient (>95%) and yielded a no carrier added product with high chemical and radionuclidic purity (>99%). Detailed comparison with previous production methods confirms that our results are superior to other reports published to date.

Calculations for the excitation functions of 3-26 MeV proton reactions on 66Zn, 67Zn and 68Zn

Calculation of excitation functions of 66Zn(p,n)66Ga, 66Zn(p,n + p)65Zn, 66Zn(p,2n)65Ga, 67Zn(p,2n)66Ga, 68Zn(p,n)68Ga, 68Zn(p,2n)67Ga natZn(p,xn)66Ga and natZn(p,xn)67Ga reactions has been carried out using the statistical and pre-equilibrium nuclear reaction models in the 3-26 MeV energy range. The calculational results are compared with the reported measurements and evaluations.