MARINA FALLONE KOSKINAS

MARINA FALLONE KOSKINAS

(Fonte: Lattes)

Resumo

Graduate at Física from Pontifícia Universidade Católica de São Paulo (1972), master's at Nuclear Engineering from Universidade de São Paulo (1978) and ph.d. at Nuclear Engineering from Universidade de São Paulo (1988). Has experience in Nuclear Engineering, focusing on Instrumentation for Measure and Control of Radiation, acting on the following subjects: radionuclide metrology, standardizations in coincidence system, determination of nuclear parameters, gamma emission probability per decay. (Text obtained from the Currículo Lattes on November 17th 2021)

Possui graduação em Física pela Pontifícia Universidade Católica de São Paulo (1972), mestrado em Tecnologia Nuclear pela Universidade de São Paulo (1978) e doutorado em Tecnologia Nuclear pela Universidade de São Paulo (1988). Atualmente é pesquisador titular do Instituto de Pesquisas Energéticas e Nucleares. Tem experiência na área de Engenharia Nuclear, com ênfase em Instrumentação para Medida e Controle de Radiação, atuando principalmente nos seguintes temas: metrologia de radionuclídeos, padronização em sistemas de coincidências, determinação de parâmetros nucleares como probabilidade de emissão gama por decaimento. (Texto extraído do Currículo Lattes em 17 nov. 2021)

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Primary standardization and Monte Carlo modeling of ( 243Am + 239Np) by means of a 4π(PC)-γ coincidence counting system
2023 - KOSKINAS, MARINA F.; MOREIRA, DENISE S.; YAMAZAKI, IONE M.; COLONNO, MARCELO; SEMMLER, RENATO; MORAIS, THALES S.L.; DIAS, MAURO S.
The procedure followed by the Nuclear Metrology Laboratory (LMN) at the IPEN for the primary standardization of a ( 243Am + 239Np) solution, in secular equilibrium, is described. The measurement was carried out in a 4π(PC) (α,β)− γ coincidence system. The total activity per unit mass of the solution was determined by the extrapolation technique, using a software coincidence counting systsem. The extrapolation curves were compared with Monte Carlo calculations by means of Code ESQUEMA, used in previous works, which, was improved and applied in order to calculate the alpha, beta, gamma, X-rays and coincidence spectra.
k0‑IPEN
2023 - 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. de
A software package for INAA (Instrumental Neutron Activation Analysis), developed at the Nuclear Metrology Laboratory of the IPEN-CNEN/SP, called k0-IPEN, is described. The package consists of a main program linked to nine subprograms designed to perform automatically most of the tasks necessary in order to obtain the mass fractions of the irradiated samples. External efficiency curves calculated by the Monte Carlo code MCNP6 can be read to extend the calibration curve to source to detector distances where only a few experimental points are available. Covariance analysis was used in all steps of the calculation. The validation of the code was tested in an intercomparison sponsored by the IAEA.
k0-IPEN
2022 - 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. de
A 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.
Experimental determination of k0 and Q0 values for 121Sb, 123Sb and 130Ba targets applying covariance analysis
2022 - BARROS, L.F.; DIAS, M.S.; KOSKINAS, M.F.
This work consists of an experimental determination of k0 and Q0 for 121Sb, 123Sb and 130Ba targets. Covariance analysis has been introduced to supply not only the overall uncertainties in these parameters but also their correlations. The irradiations were performed near the core of the IEA-R1 4.5 MW swimming-pool nuclear research reactor of the Nuclear and Energy Research Institute (IPEN-CNEN/SP), in São Paulo, Brazil. The epithermal neutron flux shape parameter, alpha, at the irradiation position is very close to zero, which favors to obtain Q0 values more accurately. Two irradiations were carried out in sequence, using two sets of samples: the first with bare samples and the second inside a Cd cover. The activity measurements were carried out in a previously calibrated HPGe gamma-ray spectrometer. The measurements were corrected for: saturation, decay time, cascade summing, geometry, self-attenuation, measuring time and mass. Standard sources of 152Eu, 133Ba, 60Co and 137Cs traceable to a 4πβ−γ primary system were used to obtain the HPGe gamma-ray peak efficiency as a function of the energy. The experimental efficiency curve was performed by a fourth-degree polynomial fit, in the energy range of the standard sources, 121–1408 keV, it contains all correlations between points. For energies above 1408 keV, the efficiencies were obtained by the Monte Carlo Method. The covariance matrix methodology was applied to all uncertainties involved. The final values for k0 and Q0 were compared with the literature.
Preliminary measurements using a Triple to Double Coincidence Ratio (TDCR) Liquid Scintillator Counter System
2021 - KOSKINAS, M.F.; KUZNETSOVA, M.; MOREIRA, D.S.; SHOUERI, R.M.; YAMAZAKI, I.M.; MORAIS, T.S.L.; SEMMLER, R.; DIAS, M.S.
The preliminary measurements using a Triple to Double Coincidence Ratio (TDCR) Liquid Scintillator Counter System, developed by the Nuclear Metrology Laboratory (LMN) at IPEN, is presented and 14C was selected to be standardized. This solution was previously calibrated by the efficiency tracing technique using a (PC)coincidence system, employing 60Co as a tracer. In order to determine the final activity, a Monte Carlo simulation was used to generate the extrapolation curve. The Software Coincidence System (SCS) developed by the LMN was used for both systems to register the events. MICELLE 2 code was used to calculate the theoretical TDCR efficiency. Measurements using HIDEX, a commercial liquid scintillator system, were also carried out and the results from the three methods were compared, showing a good agreement.
Consistency test of coincidence-summing calculation methods for extended sources
2020 - SIMA, O.; DE VISMES OTT, A.; DIAS, M.S.; DRYAK, P.; FERREUX, L.; GURAU, D.; HURTADO, S.; JODLOWSKI, P.; KARFOPOULOS, K.; KOSKINAS, M.F.; LAUBENSTEIN, M.; LEE, Y.K.; LEPY, M.C.; LUCA, A.; MENEZES, M.O.; MOREIRA, D.S.; NIKOLIC, J.; PEYRES, V.; SAGANOWSKI, P.; SAVVA, M.I.; SEMMLER, R.; SOLC, J.; THANH, T.T.; TYMINSKA, K.; TYMINSKI, Z.; VIDMAR, T.; VUKANAC, I.; YUCEL, H.
An internal consistency test of the calculation of coincidence-summing correction factors FC for volume sources is presented. The test is based on exact equations relating the values of FC calculated for three ideal measurement configurations. The test is applied to a number of 33 sets of FC values sent by 21 teams. Most sets passed the test, but not the results obtained using the quasi-point source approximation; in the latter case the test qualitatively indicated the magnitude of the bias of FC.
SUMCOR
2018 - DIAS, M.S.; SEMMLER, R.; MOREIRA, D.S.; MENEZES, M.O. de; BARROS, L.F.; RIBEIRO, R.V.; KOSKINAS, M.F.
The main features of code SUMCOR developed for cascade summing correction for volumetric sources are described. MCNP6 is used to track histories starting from individual points inside the volumetric source, for each set of cascade transitions from the radionuclide. Total and FEP efficiencies are calculated for all gamma-rays and X-rays involved in the cascade. Cascade summing correction is based on the matrix formalism developed by Semkow et al. (1990). Results are presented applying the experimental data sent to the participants of two intercomparisons organized by the ICRM-GSWG and coordinated by Dr. Marie-Cristine Lepy from the Laboratoire National Henri Becquerel (LNE-LNHB), CEA, in 2008 and 2010, respectively and compared to the other participants in the intercomparisons.
Gamma-ray impurities of 111In, 201Tl, 177Lu and 99mTc determined by means of a HPGE spectrometer
2017 - KOSKINAS, MARINA F.; ALMEIDA, JAMILLE da S.; MOREIRA, DENISE S.; SEMMLER, RENATO; DIAS, MAURO da S.
This work aims to present the radioactive impurities gamma rays emitters detected in some radiopharmaceuticals widely applied to diagnosis and therapy purposes, supplied to nuclear medicine services in Brazil by the Radiopharmaceutical Center(CR) of Nuclear and Energy Research Institute, IPEN, in São Paulo. The analysis was undertaken by means of an HPGe gamma spectrometer. The radiopharceuticals analyzed were: 111In, 201Tl, 177Lu and 99mTc.
Primary standardization of 90Sr-90Y radioactive solution
2017 - KOSKINAS, MARINA F.; MARQUES, CAIO P.; MOREIRA, DENISE S.; RAJPUT, MUHAMMAD U.; YAMAZAKI, IONE M.; DIAS, MAURO S.
In the present work, the procedure developed by the Nuclear Metrology Laboratory (LMN) at IPEN, for the primary standardization of 90Sr-90Y, is presented. The method applied has been the efficiency tracing technique using a  coincidence system. That consists in the measurement of a beta pure emitter along with a beta-gamma emitter, previously standardized, which will provide the beta efficiency. In this work, the beta-gamma emitter used was 60Co. The beta efficiency has varied using external absorbers, and the specific activity was determined using the extrapolation curve. ESQUEMA Code, which predicts the extrapolation curve by means of Monte Carlo technique, was applied, and the specific activity obtained from Monte Carlo simulation was compared with the experimental, showing good agreement within the experimental uncertainties.
Application of Monte Carlo simulation to 134Cs standardization by means of 4 ‘pi’’beta’-‘gamma’ coincidence system
2005 - TAKEDA, MAURO N.; DIAS, MAURO da S.; KOSKINAS, MARINA F.