210 likes | 311 Views
Measurements and evaluations of activation cross sections of proton and deuteron induced reactions on metals. F. T árkányi , S. Takács, F. Ditrói, B. Király, F. Szelecsényi, Z. Kovács Institute of Nuclear Research of the Hungarian Academy of Sciences (ATOMKI), Debrecen, Hungary. Topics.
E N D
Measurements and evaluations of activation cross sections of proton and deuteron induced reactions on metals F. Tárkányi, S. Takács, F. Ditrói, B. Király, F. Szelecsényi, Z. Kovács Institute of Nuclear Research of the Hungarian Academy of Sciences (ATOMKI), Debrecen, Hungary
Topics Introduction Status of charged particle activation data Experimental works Compilations and evaluations Possible contributions
Introduction Main task and profile of the Atomki Nuclear Reaction Data Group : measurement, compilation, evaluation and application of low and medium energy charged particle nuclear reaction data In the frame of international collaborations Measurement, compilation and evaluation are connected to international projects and to the every day applications at the home institute and at institutes of collaborating partners
Collaborating partner institutes Institute of Nuclear Research of the Hungarian Academy of Sciences (ATOMKI), Debrecen, Hungary Cyclotron Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium Cyclotron and Radioisotope Center (CYRIC), Tohoku University, Sendai, Japan Institute of Physics and Power Engineering (IPPE), Obninsk, Russian Federation Institut für Nuklearchemie, Forschungszentrum Jülich GmbH ( INC, FZJ), Jülich, Germany National Institute of Radiological Sciences (NIRS), Chiba, Japan iThemba Laboratory for Accelerator Based Sciences, Somerset West, South Africa
Status of proton and deuteron induced activation data (I) Aim of data measurements nuclear reaction mechanism medical isotope production accelerator technology Data producers nuclear physics laboratories radiochemistry laboratories Available experimental data mostly low energy data mostly natural target composition data only for limited products very few systematic studies database for protons is more complete
Status of proton and deuteron induced activation data (II) Quality of the data many old data with outdated monitor and decay data some new data measured with low “experience” some groups produce reliable data large systematic contradictions even in simple cases Reasons beam energy and intensity measurement target thickness and uniformity overlapping gamma-rays long target stacks unskilled researchers
Status of proton and deuteron induced activation data (III) Compilations EXFOR Landolt-Bornstein IAEA recommended databases IAEA Technical Reports ORNL CPX reports CEA Reports Activation data files
Status of proton and deuteron induced activation data (IV) Very few evaluations for CP activation Methods: fit with analytical functions and theoretical models Importance of critically selected experimental data Very few experiment for validation No uncertainties available Quality of evaluated data, missing upgrade IAEA co-ordination role
Experimental worksSystematic measurement of excitation functionsof charged particle induced reactions for many different applications Production of medical radioisotopes for diagnostics and for therapy Excitation functions of monitor reactions Activation cross sections for accelerator technology (waste transmutation, IFMIF, target technology) Activation cross sections for Thin Layer Activation (TLA) Activation cross sections for charged particle activation analysis
Experimental technique Activation method Stacked foil technique External beam of a cyclotron Commercial and self-prepared targets Stacked beam monitor foils in the whole energy range X- and gamma-ray spectroscopy Iterative data evaluation Important role of theoretical results in the data evaluation
Stacked foil irradiation technique Advantages effective use of accelerator same beam current good relative accuracy Disadvantages cumulating energy uncertainties beam broadening cooling problems detector capacity
Theoretical calculations to check the prediction capability of different model codes using a priori calculations to have a preliminary knowledge on the behaviour of the excitation functions before the experiment and during the data evaluation to evaluate contradicting experimental data measured earlier (effective threshold energies, energy shifts, significant differences in absolute values) to estimate contributions from nuclear reactions on different stable isotopes of the given element and from parent decays in the case of cumulative processes to estimate radionuclide impurities from residual nuclei having unfavourable decay characteristics (large T1/2, no gamma, etc.) to prepare recommended database mostly ALICE-IPPE code but in a few cases the EMPIRE-II, GNASH and TALYS codes
Results Cross section data of proton and deuteron induced reactions for 38 metallic elements Cross section data for production of about 450 radionuclides
Recommended cross section data to monitor charged particle beam parameters (energy, intensity)22 reactions (IAEA CRP 1995-1999)Recommended cross sections and integral yields for production of diagnostic medical radioisotopes for SPECT and PET studies17 reactions (IAEA CRP 1995-1999)Recommended cross sections and integral yields for production of therapeutic radioisotopes35 reactions (IAEA CRP 2003-2007)Recommended database for wear studies by using charged particle induced Thin Layer Activation Technique (in progress)Database for charged particle activation of targets used for isotope production (in progress) Compilations and evaluations
Measurement of missing experimental data taking into account the irradiation possibilitiesCompilation of literature experimental data Critical evaluation of the experimental databaseSelection of reliable datasetsParticipation in the preparation of recommended datasets (cross section, integral yield) in collaboration with theoretical groupsValidation of recommended data sets with integral measurements Possible contributions to FENDL-3