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Formation of Sc radioisotopes under the irradiation of titanium of natural isotopic composition by bremsstrahlung photons with energies up to 55 MeV was studied. The yield of 47Sc is 5·105 Bq/μA h (g/cm2). Inevitable impurities are 46Sc and 48Sc (1.5% and 9.1% of 47Sc radioactivity at EOB, respectively). 47Sc was separated by extraction chromatography on a DGA resin in HNO3 and HCl media. The separation procedure takes about 2 h, the radiochemical efficiency was > 97%. The result was compared with other photonuclear experiments on titanium nuclei. It is shown that the photonuclear method can be used for the production of therapeutic amounts of 47Sc. [ABSTRACT FROM AUTHOR]

Production of medical radionuclide 67Cu by the irradiation of Zn of natural isotopic composition by bremsstrahlung photons of maximum energy of 55 MeV was studied. Production yields of 67Cu and other activation products were determined. The yield of 67Cu is (2.34 ± 0.07) × 105 Bq/(μA h g/cm2) at EOB. The experimental data were compared with the results of other experiments and theoretical calculations based on the statistical model in the TALYS software and on the combined model of photonuclear reactions. Technique of chemical separation of 67Cu from irradiated zinc target based on extraction chromatography using CU Resin was applied. Radiochemical yield was > 95%, separation time was 1 h. The possibility of production of medical quantities was discussed. [ABSTRACT FROM AUTHOR]

The possibility of production a medical radionuclide 177Lu by irradiating natHfO2 by bremsstrahlung photons up to 55 MeV was investigated. The yields of the main nuclear reactions were measured. A procedure for one-step separation of carrier free 177Lu via extraction chromatography on the LN resin sorbent (Triskem) was developed. The radiochemical yield was 98%, separation factor was higher than 105. Isomeric ratio 177mLu/177Lu was estimated. Simulation of 177Lu production in photonuclear reactions on 178Hf, 179Hf and natHf nuclei was performed. The possibility of production of medical quantities was discussed. [ABSTRACT FROM AUTHOR]

In our work, the photonuclear production of 198,199Au isotopes for nuclear medicine purposes was studied, and a method for their recovery from irradiated mercury was developed. The yields of the corresponding nuclear reactions were determined, and a comparison of various methods of obtaining gold radioisotopes was provided. New sorbents based on benzo-15-crown-5, which selectively binds gold, were studied, and the optimal conditions for Au recovery with a high degree of purification from mercury were found. It was established that, for the fast and quantitative recovery of Au isotopes, it was necessary to add at least 0.1 mg of the carrier. As a result, the developed method can be regularly used to obtain 198,199Au for the research of radiopharmaceuticals based on them. [ABSTRACT FROM AUTHOR]

A new method of production of one of the most widely used isotopes in nuclear medicine, 177Lu, with high chemical purity was developed; this method includes irradiation of the HfO2 target with bremsstrahlung photons. The irradiated target was dissolved in HF and then diluted and placed onto a column filled with LN resin. Quantitative sorption of 177Lu could be observed during this process. The column later was rinsed with the mixture of 0.1 M HF and 1 M HNO3 and then 2 M HNO3 to remove impurities. Quantitative desorption of 177Lu was achieved by using 6 M HNO3. The developed method of 177Lu production ensures high purification of this isotope from macroquantities of hafnium and zirconium and radioactive impurities of carrier-free yttrium. The content of 177mLu in 177Lu in photonuclear production was determined. Due to high chemical and radionuclide purity, 177Lu obtained by the developed method can be used in nuclear medicine. [ABSTRACT FROM AUTHOR]

Single- and multi-photon spectra of pulsed γ -ray beams produced at 17, 34, and 40 MeV in the laser Compton scattering were measured with an 8” × 12” NaI(Tl) detector. By using the experimental single-photon spectra as the probability function of generating random numbers, response functions of the NaI(Tl) detector to j -fold photons ( j = 2, 3, 4 ...) were constructed. The least-square fits to the experimental multi-photon spectra by the Poisson distribution consisting of the response functions were made. The multi-photon spectra measured at 17 and 34 MeV follow the Poisson distribution. A quenching phenomenon of multi-photon spectra was observed for 40 MeV γ -rays as a result of the saturation at the photomultiplier tube of the NaI(Tl) detector. The original Poisson distributions were restored from the quenched spectra using a saturation curve in the form of y = a ⋅ x η with η =e − b x . We discuss the accuracy of photon-flux determination. [ABSTRACT FROM AUTHOR]

A novel technique of direct neutron-multiplicity sorting with a flat-efficiency detector is proposed to resolve the long-standing discrepancy between the Livermore and Saclay data of partial photoneutron cross sections. A flat-response neutron detector with the detection efficiency of 36 . 5 ± 1 . 6 % over a neutron energy range 0.01–5.0 MeV was developed by optimizing triple-ring configurations of He proportional counters embedded in a polyethylene moderator. The technique forms a foundation of measuring cross sections with x = 1 − 3 for the photonuclear data project of the International Atomic Energy Agency. The methodology of direct neutron-multiplicity sorting and key experimental elements are presented. [ABSTRACT FROM AUTHOR]

Intense, quasi-monochromatic, polarized γ -ray beams with high and tunable energy produced by Compton scattering of laser photons against relativistic electrons are used for fundamental studies and applications. Following a series of photoneutron cross section measurements in the Giant Dipole Resonance (GDR) energy region performed at the NewSUBARU synchrotron radiation facility, we have developed the eliLaBr Monte Carlo simulation code for characterization of the scattered γ -ray photon beams. The code is implemented using Geant4 and is available on the GitHub repository (https://github.com/dan-mihai-filipescu/eliLaBr). Here we report the validation of the eliLaBr code on NewSUBARU LCS γ -ray beam flux and spectral distribution data and two applications performed with it for asymmetric transverse emittance profiles electron beams, characteristic for synchrotrons. The first application is based on a systematic investigation of transverse collimator offsets relative to the laser and electron beam axis. We show that the maximum energy of the LCS γ -ray beam is altered by vertical collimator offsets, where the edge shifts towards lower energies with the increase in the offset. Secondly, using the eliLaBr code, we investigate the effect of the laser polarization plane orientation on the properties of the LCS γ -ray beams produced with asymmetric emittance electron beams. We show that: 1. The use of vertically polarized lasers contributes to the preservation of the LCS γ -ray beam maximum energy edge by increasing the precision in the vertical collimator alignment. 2. Under identical conditions for the electron and laser beams phase-space distributions, the energy spectrum of the scattered LCS γ -ray beam changes with the laser beam polarization plane orientation. More precisely, the use of vertically polarized laser beams slightly deteriorates the LCS γ -ray beam energy resolution. [ABSTRACT FROM AUTHOR]

Nowadays, cobalt isotopes 55Co, 57Co, and 58mCo are considered to be promising radionuclides in nuclear medicine, with 55Co receiving the most attention as an isotope for diagnostics by positron emission tomography. One of the current research directions is dedicated to its production using electron accelerators (via photonuclear method). In our work, the yields of nuclear reactions occurring during the irradiation of natNi and 60Ni by bremsstrahlung photons with energy up to 55 MeV were determined. A method of fast and simple cobalt isotopes separation from irradiated targets using extraction chromatography was developed. [ABSTRACT FROM AUTHOR]

Photoneutron measurements in the Giant Dipole Resonance region have been recently performed using quasimonochromatic Laser Compton Scattering γ -ray beams at NewSUBARU (Japan) for 59Co, 89Y, 103Rh, 139La, 159Tb, 165Ho, 169Tm, 181Ta, 197Au and 209Bi. Experimental (γ , x n) with x = 1–4 photoneutron cross sections have been obtained with a direct neutron-multiplicity sorting method associated to a flat-efficiency neutron detector, which operates under single firing conditions obtained by low reaction rates. In this paper, we discuss recent developments to the neutron-multiplicity sorting procedure dedicated to (i) resolving multiple firing events and to (ii) extracting the average energies of (γ , x n) photoneutrons. The method is tested on 159Tb experimental data. [ABSTRACT FROM AUTHOR]