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The 67Cu is considered as one of the most perspective radio isotopes in targeted radio-immunotherapy medical applications. 67Cu is a β–-emitter with a mean β– energy, which allows treating tumors in size up to about 4 mm. Its decay is followed by emission of low energy gamma-rays suitable for gamma-camera imaging. The about three days half-life (T 1/2 = 61.83 h) is optimal for human applications. However, one of the main drawback factors for its application is still the limited supply of 67Cu. There are several possibilities to produce 67Cu. High flux reactors, charged particle accelerators and high-energy bremsstrahlung radiations can be used to produce 67Cu. In this work we have studied one of the promising charged particle production routes based on the 64Ni(α,p)67Cu nuclear reaction. Cross sections for formation of 67,64,61,60Cu, 62,63Zn and 56,57Ni were studied up to 50 MeV alpha-particle energy on nickel targets with natural isotopic composition. [ABSTRACT FROM AUTHOR]

Abstract We measured cross sections of deuteron-induced reactions on a niobium target up to 24 MeV using the stacked-foil activation technique and off-line γ-ray spectrometry. The production cross sections of 93mMo, 92mNb and 89Zr were determined. The results were compared with the experimental data studied earlier and the predictions of theoretical calculations. [ABSTRACT FROM AUTHOR]

Highlights • Alpha induced nuclear reactions on natural silver in the 40–50 MeV region. • Stacked foil irradiation technique. • Comparison with the EMPIRE 3.2 and TENDL-2017 calculations. • Physical yield. • Thin Layer Activation. Abstract Natural silver targets have been irradiated by using a 50 MeV alpha-particle beam in order to measure the activation cross sections of radioisotopes in the 40–50 MeV energy range. Among the radio-products there are medically important isotopes such as 110mIn and 111In. For optimizing the production of these radioisotopes and regarding their purity and specific activity the cross section data for every produced radioisotope are important. New data are measured in this energy range and the results of some previous measurements have been confirmed. Physical yield curves have been calculated by using the new cross section data completed with the results from the literature. [ABSTRACT FROM AUTHOR]

117m Sn is one of the radioisotopes can be beneficially produced through alpha particle irradiation. The targets were prepared by deposition of 116 Cd metal onto high purity 12 μm thick Cu backing. The average deposited thickness was 21.9 μm. The beam energy was thoroughly measured by Time of Flight (TOF) methods and proved to be 51.2 MeV. For the experiment the well-established stacked foil technique was used. In addition to the Cd targets, Ti foils were also inserted into the stacks for energy and intensity monitoring. The Cu backings were also used for monitoring and as recoil catcher of the reaction products from the cadmium layer. The activities of the irradiated foils were measured with HPGe detector for gamma-ray spectrometry and cross section values were determined. As a result excitation functions for the formation of 117m Sn, 117m,g In, 116m In, 115m In and 115m,g Cd from enriched 116 Cd were deduced and compared with the available literature data and with the results of the nuclear reaction model code calculations EMPIRE 3.2 and TALYS 1.8. Yield curves were also deduced for the measured nuclear reactions and compared with the literature. [ABSTRACT FROM AUTHOR]

Activation cross sections of the α-particle-induced reactions on natCr were measured. A stacked foil activation technique and γ-ray spectrometry were used. Nickel-chromium alloy, nickel and titanium metallic foils were stacked as a target. The target was irradiated with a 51.2-MeV α-particle beam at the AVF cyclotron, RIKEN. The γ rays were measured for the irradiated foils using an HPGe detector. Production cross sections of 52gFe, 52g,54Mn, 48,51Cr and 48V radionuclides were determined. The cross sections determined in this experiment were compared with the literature data and found to be consistent with them. [ABSTRACT FROM AUTHOR]

Cross sections of alpha-particle induced reactions were determined on antimony targets using alpha-particle irradiation with a primary energy of 50 MeV. The standard stacked target technique, activation method and offline gamma-ray spectrometry were applied for determination of the reaction cross sections. Thin Sb targets prepared by vacuum evaporation onto Kapton backings were activated. Ti foils were inserted into the stack for monitoring the alpha-particle beam parameters and energy loss of the particles in the target by using the natTi(α,x)51Cr monitor reaction. Reaction cross sections for formation of 121,123,124,125,126I, 121m,g,123m,125mTe and 118m,120m,122gSb were determined and compared to the available literature data and theoretical estimation of the cross sections from the TENDL-2019 data library. [ABSTRACT FROM AUTHOR]

We developed a multi-segmented proportional gas counter to perform β -decay spectroscopy of neutron-rich nuclei extracted from KEK Isotope Separation System (KISS). The 32 segmented gas counters allow us two-dimensional tracking of the events to identify β -ray events by discriminating background events. The detectors being by low-density material of thin aluminized Mylar foils and P10 gas enabled us to detect low energy electrons down to 100 keV. The absolute detection efficiency was 45% at Q β = 1 MeV, and the measured background event rate was 0.11 cps. The detector was applied to perform β -decay spectroscopy and hyperfine structure measurements of neutron-rich isotopes of Pt, Ir, and Os. We started to develop the gas counter with three-dimensional tracking by replacing the material of anode wire from BeCu to resistive thin carbon to reduce the background event rate below 0.01 cps. [ABSTRACT FROM AUTHOR]

An experiment of α -induced reactions on yttrium-89 was performed to investigate the excitation functions of 89 Zr and 90 Nb , which are suitable for immuno-PET studies. The stacked-foil method, activation technique, and off-line γ -ray spectrometry were used for this investigation. The excitation functions of 92 m , 91 m , 89 m , 89 g Nb , 88 Zr , and 90 m , 88 g , 87 m , 87 g Y were also derived and compared with earlier experimental and the TENDL-2017 data. Good agreements with part of the previous studies were found. [ABSTRACT FROM AUTHOR]

Activation cross sections induced by 50 MeV alpha-particle beam on natural tantalum were measured at the AVF cyclotron of the Nishina Center of RIKEN. The well-established stacked target technique and activation method were applied followed by high-resolution gamma spectrometry to determine the reaction cross sections. The experiment aimed to determine activation cross sections for the longer-lived reaction product. Accordingly, activation cross sections were deduced for the formation of 181, 182m, 182g, 183, 184m, 184gRe and 178g, 182gTa. [ABSTRACT FROM AUTHOR]

The activation cross sections of the alpha-particle induced reactions on natural palladium were determined up to 50 MeV using the stacked-foil technique and high-resolution gamma-ray spectrometry. Production cross sections of 111m,109,107,105,104Cd and 111g,110m,106m,105g,103gAg were obtained. The results were compared with the data of previous experiments and results of theoretical model calculations. [ABSTRACT FROM AUTHOR]

The production cross sections of 68,69 Ge and 66,67 Ga by α-induced reactions on nat Zn have been measured using the stacked-foil activation method and off-line γ-ray spectrometry from their threshold energies to 50.7 MeV. The derived cross sections were compared with the previous experimental data and the calculated values in the TENLD-2017 library. Our result shows a slightly larger amplitude than the previous data at the peak, though the peak energy is consistent with them. [ABSTRACT FROM AUTHOR]

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

Various isotopes of Ac, Ra, Fr, and Rn were produced by fusion-evaporation reactions using a 48 Ca beam. The energetic ions were stopped in and extracted from a helium gas cell. The extracted ions were identified using a multi-reflection time-of-fight mass spectrograph. In all cases, it was observed that the predominant charge state for the extracted ions, including the alkali Fr, was 2+. [ABSTRACT FROM AUTHOR]

Selected reactions with well-defined excitation functions can be used to monitor the parameters of charged particle beams. The frequently used reactions for monitoring alpha particle beams are the 27 Al(α,x) 22,24 Na, nat Ti(α,x) 51 Cr, nat Cu(α,x) 66,67 Ga and nat Cu(α,x) 65 Zn reactions. The excitation functions for these reactions were studied using the activation method and stacked target irradiation technique to crosscheck and to compare the above six reactions. Thin metallic foils with natural isotopic composition and well defined thickness were stacked together in sandwich targets and were irradiated at the AVF cyclotron of RIKEN with an alpha particle beam of 51.2 MeV. The activity of the target foils were assessed by using high-resolution gamma spectrometers of high purity Ge detectors. The data sets of the six processes were crosschecked with each other to provide consistent, cross-linked numerical cross section data. [ABSTRACT FROM AUTHOR]

The cross sections of alpha particles induced nuclear reactions on natural germanium were investigated by using the standard stacked foil target technique, the activation method and high resolution gamma spectrometry. Targets with thickness of about 1 μm were prepared from natural Ge by vacuum evaporation onto 25 μm thick polyimide (Kapton) backing foils. Stacks were composed of Kapton-Ge-Ge-Kapton sandwich target foils and additional titanium monitor foils with nominal thickness of 11 μm to monitor the beam parameters using the nat Ti(α,x) 51 Cr reaction. The irradiations were done with E α = 20.7 and E α = 51.25 MeV, I α = 50 nA alpha particle beams for about 1 h. Direct or cumulative activation cross sections were determined for production of the 72,73,75 Se, 71,72,74,76,78 As, and 69 Ge radionuclides. The obtained experimental cross sections were compared to the results of theoretical calculations taken from the TENDL data library based on the TALYS computer code. A comparison was made with available experimental data measured earlier. Thick target yields were deduced from the experimental cross sections and compared with the data published before. [ABSTRACT FROM AUTHOR]

In order to investigate nuclei produced via fusion–evaporation reactions, especially super-heavy elements (SHE), we have begun construction of a facility for conversion of fusion–evaporation residues (EVR) to low-energy beams. At the base of this facility is a small cryogenic gas cell utilizing a traveling wave RF-carpet, located directly following the gas-filled recoil ion separator GARIS-II, which will thermalize EVRs to convert them into ion beams amenable to ion trapping. We present here the results of initial studies of this small gas cell. [ABSTRACT FROM AUTHOR]

As nuclear medicine community has shown an increasing interest in accelerator produced 99m Tc radionuclide, the possible alternative direct production routes for producing 99m Tc were investigated intensively. One of these accelerator production routes is based on the 100 Mo(p,2n) 99m Tc reaction. The cross section of this nuclear reaction was studied by several laboratories earlier but the available data-sets are not in good agreement. For large scale accelerator production of 99m Tc based on the 100 Mo(p,2n) 99m Tc reaction, a well-defined excitation function is required to optimise the production process effectively. One of our recent publications pointed out that most of the available experimental excitation functions for the 100 Mo(p,2n) 99m Tc reaction have the same general shape while their amplitudes are different. To confirm the proper amplitude of the excitation function, results of three independent experiments were presented (Takács et al., 2015). In this work we present results of a thick target count rate measurement of the E γ = 140.5 keV gamma-line from molybdenum irradiated by E p = 17.9 MeV proton beam, as an integral benchmark experiment, to prove the cross section data reported for the 100 Mo(p,2n) 99m Tc and 100 Mo(p,pn) 99 Mo reactions in Takács et al. (2015). [ABSTRACT FROM AUTHOR]

A multiple target He/PbI2 aerosol jet system coupled with a thermal ion source was installed in the isotope separator on line (JAERI-ISOL) at the JAERI tandem accelerator facility. The neutron-deficient americium and curium isotopes produced in the 233,235U(6Li, xn) and 237Np(6Li, xn) reactions were successfully mass-separated and the overall efficiency including the ionization of Am atoms was evaluated to be 0.3–0.4%. The identification of a new isotope 237Cm with the present system is reported. [Copyright &y& Elsevier]