DENISE SIMÕES MOREIRA
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Resumo IPEN-doc 28957 k0-IPEN2022 - DIAS, MAURO da S.; SEMMLER, RENATO; KOSKINAS, MARINA F.; MOREIRA, DENISE S.; YAMAZAKI, IONE M.; BRANCACCIO, FRANCO; BARROS, LIVIA F.; RIBEIRO, RAFAEL V.; MORAIS, THALES S.L. deA new software package for INAA, developed at the Nuclear Metrology Laboratory (LMN) of the Nuclear and Energy Research Institute (IPEN-CNEN/SP), called k0-IPEN, is described. The package consists of a main program linked to nine subprograms designed to perform automatically all the tasks necessary in order to obtain the mass fractions of the irradiated samples. The goals of these nine routines are: a) to calculate the experimental peak efficiencies and P/T ratios for the standard sources, together with all the corresponding uncertainties; b) to correct the peak efficiencies for coincidence summing; c) to fit the peak efficiencies and P/T ratios with log-log polynomial functions; d) to determine experimentally the and f parameters by the Triple Bare and by the Cd Ratio Multimonitor Methods; e) to correct for interferences; f) to determine the average mass fractions, taking into account the correlations among all partial uncertainties involved. In the present version, the only data that must be inserted as input parameter, externally from the package, are the self-shielding correction factor, which is calculated by the MATSSF code, and the geometry factor that corrects for the difference between sizes of standard sources and measured samples. The code can deal with different spectrum formats such as CHN, SPE and CNF. The routine designed to calculate the peak areas has a simple algorithm and is not yet capable of separating multiplets. Therefore, it is suitable for analysing separated peaks, such as those found in standard calibration source measurements. However, for complex spectra, the code can read peak list files obtained from other codes, such as HyperMet or HyperLab. External efficiency curves calculated by the Monte Carlo code MCNP6 can be read to extend the calibration curve to regions where there are only a few experimental points available. The code k0-IPEN is being tested and its validation accomplished by means of an intercomparison sponsored by the IAEA, and presented at this conference.Resumo IPEN-doc 24574 Disintegration rate and gamma-ray emission probability per decay measurement of Cu-642017 - KOSKINAS, M.F.; YAMAZAKI, I.M.; MOREIRA, D.S.; TAKEDA, M.N.; DIAS, M.S.This work aims to present the 64Cu standardization method developed in the Nuclear Metrology Laboratory (LMN) at the IPEN-CNEN/SP, using a 4 coincidence system, and the measurement of the gamma-ray emission probabilities per decay of 1345.7 keV of 64Cu by means of a REGe gamma-ray spectrometer. The 4 coincidence system consists of a gas- flow proportional counter with 4 geometry and using 90% Ar + 10% CH4 gas at 0.1 MPa, as the detector, coupled to two NaI(Tl) crystal for the gamma-ray emission detection. The events were registered by means of a Time to Amplitude Converter (TAC) associated with a Multi-Channel Analyzer. Two gamma-ray windows were set for the coincidence measurements, one including the positron-annihilation quanta and the other located at the total absorption energy peak of the 1345.7 keV gamma-ray transition. The 64Cu was obtained by irradiating 0.3mg of metallic cooper in the IEA-R1 research reactor under a 1 1013 cm2 s1 thermal neutrons flux. To obtain the 64Cu solution the foil irradiated was dissolved in 20 L of HNO3 65% and after that was diluted in 20 mL of 0.1M HCl. The activity was determined by means of the extrapolation curve from eight irradiations, normalized by means of the germanium measurements. The Kawada factor to correct the inefficiency for beta plus and beta minus in the N4 has been applied. The gamma-ray full efficiency peak curve of the germanium spectrometer was measured at 17.9 cm of source-detector distance, in the energy range from 244 keV to 2754 keV, by measuring flamed-sealed ampoules of 24Na, 60Co, 133Ba, 137Cs, and 152Eu standardized at the LMN. The sample for measurement in the spectrometer was prepared in flame-sealed ampoule with 1 mL of the diluted solution. The gamma-ray emission probability per decay of the 1345.7 keV transition of 64 Cu was (0.472 0.010)%, in agreement with the literature.Resumo IPEN-doc 04755 Determinacao da taxa de desintegracao do Y-881996 - SIMOES, D.; KOSKINAS, M.F.; DIAS, M.S.