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Theoretical Models and Relevant Calculations of Photon Production and Photonuclear Reaction Data
No full textPhoton 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 considered in the present ENEA evaluations, aimed at producing specific contributions to the above-mentioned nuclear programs and applications and at cooperating in the framework of the international initiatives and efforts on the inter-comparison of the evaluated data and of the relevant models and codes. An innovative method has been developed and utilized for microscopic and statistical models of nuclear structure, especially referring to algebraic models aimed at complementing the reaction models for the treatment of pre-equilibrium and compound-nucleus processes. The relevant microscopic algebraic model calculations are discussed, as they reasonably approximate the observed structure of photonuclear cross sections due to multi-polarity effects. Accordingly, theoretical calculation methods are presented for Ti and Mo isotopes, as materials relevant to nuclear applications, and significant results are reviewed for Ti natural isotopes and the element in comparison with the experimental data when available from the existing literature
Decay heat estimate based on EAF-2003 and FENDL/A-2 nuclear data libraries for fusion relevant materials in comparison with FNS-JAERI experiments
No full textResults are presented on activation data analyses for materials of main relevance to fusion technology, referring to the activation data libraries EAF-2003 and FENDL/A-2 and to the FENDL/D-2 decay data library and to the relevant calculations performed with the European activation code ANITA-2000. The comparison is presented and discussed of these calculations with respect to integral decay heat measurements performed at the Fusion Neutronics Source FNS, JAERI, Tokai, Japan, with the aim to validate the same activation nuclear data by the adopted computational approach. The neutron flux distributions into the material samples were provided by JAERI as results of experiment simulations through the 3D Monte-Carlo MCNP transport code
Experimental results and model calculations of excitation functions relevant to the production of specific radioisotopes for metabolic radiotherapy and for PET
No full textFirst results are given from the comparison of experimental values and model calculations on accelerator-produced high specific activity radionuclides in no-carrier-added (NCA) form. The relevant radioisotopes are : Cu-64, produced by Zn-nat(d, alphaxn) and Zn-nat(d,2p) reactions, for simultaneous positron/negatron metabolic radiotherapy and PET imaging; Ga-66 high-energy positron emitter (4.2 MeV), produced by Zn-nat(d,xn) reactions, for metabolic radiotherapy and for PET: Re-186g, produced by W-186(p,n) and W-186(d,2n) reactions, for negatron (1.1 MeV) metabolic radiotherapy; At-211/Po-211, produced by Bi-209(alpha,2n) reaction (with spike of gamma emitter At-210 produced by Bi-209(alpha,3n) reaction) and Ac-225/Bi-213/Po-213 produced by Ra-226(p,2n) reaction, both for high-LET radiotherapy
Radioanalytical techniques based on the use of very High Specific Activity "No Carrier Added" radionuclides
No full textA rapid improved method for gamma spectrometry determination of thallium-202 impurities, in [thallium-201]labelled radiopharmaceuticals
No full textA competitive method for simultaneous deuteron-cyclotron production of No-Carrier-Added copper-64 and gallium-67,66 for applications in PET radiodiagnostic and metabolic therapy of tumours
No full textExperimental thin-target and thick-target yields for natOs(alpha,xn)Pt, natOs(alpha,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
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
A new alpha-emitter for nuclear medicine: U-230
No full textThe limited number of radionuclides emitting alpha-particles and their limited availability is discussed. A new alpha-emitter 230U (T1/2 = 20.8 d, 100% a) is suggested and its preparation from thorium target bombarded by accelerated protons (via initial formation of 230Pa (T1/2 = 17.4 d, 8.4% decay to 230U)), or 4He is discussed. The Empire II model was used to calculate the excitation functions for the different products from bombardment of Th by protons. The calculated thick target yield for 230Pa is 0.6 mCi/mA . h, leading to about 24 mCi/mA . h of 230U or about 150 mCi/mA . h in the case of alpha-bombardment
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