E. Menapace

Thin-target excitation functions and optimization of simultaneous production of NCA copper-64 and gallium-66,67 by deuteron induced nuclear reactions on a natural zinc target

Copper-64 is a radionuclide suitable for labeling of a wide range of radiopharmaceuticals for PET imaging, as well as systemic or local radioimmunotherapy of tumors. Among the possible methods for cyclotron production of No Carrier Added (NCA) 64Cu (61Cu), we investigated the deuteron irradiation on natural Zn target, via (d,axn) and (d,2pxn) nuclear reactions. This paper reports the preliminary results about the experimental determination and theoretical calculation of thin-target excitation functions in the energy range up to 19 MeV for 61Cu, 64Cu, 66Ga, 67Ga, 65Zn and 69mZn. A fast selective radiochemical separation of NCA 64Cu from Zn target and Ga radionuclides, with quality control tests is described too.

Comparison between Theoretical Calculation and Experimental Results of Excitation Functions for Production of Relevant Biomedical Radionuclides

The radionuclide production for biomedical applications has been brought up in the years, as a special nuclear application, at INFN LASA Laboratory, particularly in co‐operation with the JRC‐Ispra of EC. Mainly scientific aspects concerning radiation detection and the relevant instruments, the measurements of excitation functions of the involved nuclear reactions, the requested radiochemistry studies and further applications have been investigated. On the side of the nuclear data evaluations, based on nuclear model calculations and critically selected experimental data, the appropriate competence has been developed at ENEA Division for Advanced Physics Technologies. A series of high specific activity accelerator‐produced radionuclides in no‐carrier‐added (NCA) form, for uses in metabolic radiotherapy and for PET radiodiagnostics, are investigated. In this work, last revised measurements and model calculations are reviewed for excitation functions of natZn(d,X)64Cu, 66Ga reactions, referring to irradiation...

Thick target yield measurement of 211At through the nuclear reaction 209Bi(?, 2n)

Radionuclide Therapy (RNT) and Radioimmunotherapy (RIT) are potentially of great interest for cancer therapy. In many therapeutic applications alpha emitters should be much more effective than already-approved beta emitters due to the short range and high linear energy transfer of alpha particles. 213Bi is an important alpha emitter already used in clinical trials but the half-life of this radioisotope is short (46 minutes) and so its use is limited for certain therapies. 211At is potentially very interesting for medical purposes because of its longer half-life of 7.2 hours, and suitable decay scheme. We have studied the cyclotron-based production of 211At via the reaction 209Bi(?, 2n), this production route probably being the most promising in the long term. The energy dependence of thick target yields and the reaction cross sections for the production of 211At and 210At were determined and found to be in good agreement with literature. The best energy to produce 211At is 28-29 MeV. The possible production of the undesired, highly radiotoxic, and long-lived alpha-emitting 210Po (138.38 days), which is produced from decay of 210At, is also discussed.

Determination of 125I impurities in [123I]labelled radiopharmaceuticals, by liquid scintillation counting: Sensitivity of the method

Abstract Iodine-125 is a radioisotopic impurity “always” present in iodine-123, produced by nuclear reactions induced either on natural or “highly” enriched targets. Liquid scintillation counting is a very sensitive tool to determine low level impurities of both low energy electrons and photons in aqueous and organic solutions of radiopharmaceutical compounds. With this technique it was possible to determine, on commercial samples, that the content of 125I was of the order of not less than 0.1% for 123I produced via 127I(p,5n) reactions and not less than 0.01% for 123I produced via “highly” enriched 124Xe(p,X) nuclear reactions.

Energy and parity dependence of nuclear level densities for structural materials

Abstract The parity distribution of nuclear excited states is investigated in the frame of a statistical microscopic Nilsson-BCS formalism. Calculations performed for medium-mass nuclei (51≤A≤66) show that the parity equiprobability holds at excitation energies greater than 15 MeV, in agreement with the experimental information.

Nuclear photoreactions in the context of a nuclear data review for radiation shielding in advanced technology applications

Theoretical results are presented on nuclear photoreaction calculations, based on algebraic models of the nuclear structure, relevant to advanced technology applications, mainly in the intermediate energy region, such as those related to accelerator applications, particularly to shielding studies concerning Accelerator Driven Systems (ADS), intense neutron spallation sources and also electron accelerators (including free electron lasers and advanced synchrotron radiation facilities applications) as well as for medical purposes. The present results are discussed within a review of the international co-operation for nuclear data for radiation shielding, carried out at ENEA. In particular, the contributions are presented to the SATIF initiative and to the related co-operation activities on shielding aspects of accelerators and irradiation facilities, according to the NEA Nuclear Science Committee (NSC) advice, to JEFF project and NSC-WPEC relevant activities, concerning microscopic nuclear data evaluation and validation.

Review of Contributions to the International Co-operation on Nuclear Data for Radiation Shielding

Contributions to the international co-operation initiatives relevant to nuclear data for radiation shielding are reviewed, with reference to the activities in the field at ENEA in the past years and recently and to the related results, following the requests in the context of fission and fusion reactor studies and projects and of accelerator applications, in particular for research and advanced radiotherapy purposes. In particular, the relationships are pointed out with the NEA initiatives, according to the Nuclear Science Committee advice, concerning the relevant microscopic nuclear data and their validation with respect to integral benchmark experiments, and the co-operation activities on shielding aspects of the accelerators.

Theoretical Models and Relevant Calculations of Photon Production and Photonuclear Reaction Data

Photon production and photonuclear reaction data, with emphasis on theoretical model aspects aimed at reliable evaluations, represent a challenge in many technological applications, from radiation shielding for different nuclear systems, including accelerators, to devices relevant to nuclear energy applications, particularly the ones concerning the Accelerator Driven Systems for nuclear waste transmutation. In this field of applied science, theoretical calculations complementing the existing experimental data play an essential role in performing valuable nuclear data evaluations, particularly when the measured quantities are discrepant, scarce, or even lacking. In this framework, new improved results of theoretical and evaluation activities carried out at ENEA, Division for Advanced Physics Technologies, are presented especially concerning photonuclear reaction cross sections. Relevant aspects of nuclear structure models are discussed together with a critical analysis of the related computing codes consid...

Experimental Thin-Target and Thick-Target Yields for natOs(α, xn)Pt, natOs(α, X)Os, Ir and natMo(p, xn)Tc Nuclear Reactions from Threshold up to 38 and 45 MeV, by Combined Single and Stacked Foil Techniques

The experimental values of thin-target excitation functions for the nuclear reactions: natOs(α,X)188,189,191 Pt,192g, 194mIr in the energy range 11-38 MeV and natMo(p,xn)94g,95g,95m,96(m+g)Tc in the energy range 5-44 MeV are presented. The experimental values were obtained by cyclotron activation followed by off-line HPGe γ-spectrometry and corrected at the End Of an Instantaneous Bombardment, EOIB. In different cases use was made of single foil and stacked foil techniques, which present significantly different advantages and disadvantages. The thintarget yield values can be easily either numerically or analytically integrated, as a function of both incoming particle energy and energy loss in target itself, in order to calculate apriori the thick-target yield of various radionuclides under any different experimental condition. Moreover, the thin-target yields are directly related to the effective cross-sections of various nuclear reaction channels involved. The data are of relevant interest for optimizing cyclotron production of platinum and technetium radionuclides to be used as radiotracers for metallo-biochemical, biomedical, toxicological and environmental studies.