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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Determinação de K0 e Q0 para as reações 74Se(n,γ) 75Se, 113In(n,γ) 114MIn, 186W(n,γ) 187W e 191Ir(n,γ) 192Ir
2022 - BARROS, LIVIA F.; DIAS, MAURO da S.; KOSKINAS, MARINA F.
Este trabalho teve o intuito de contribuir para a melhoria na qualidade dos valores de k0 e Q0 para as reações 74Se(n,γ)75Se, 113In(n,γ)114mIn, 186W(n,γ)187W e 191Ir(n,γ)192Ir. As medições das amostras irradiadas no reator IEA-R1 e das fontes padrão da Agência Internacional de Energia Atômica (IAEA, do inglês International Atomic Energy Agency) foram realizadas por espectrometria gama de alta resolução em detector de HPGe. A fim de investigar melhor as eficiências nos intervalos de energia em que não havia pontos experimentais, foi aplicado o Método de Monte Carlo. As contribuições originais deste trabalho foram: a análise de covariância associada ao Método dos Mínimos Quadrados, que foi utilizada para o tratamento adequado das incertezas para as reações 74Se(n,γ)75Se, 113In(n,γ)114mIn, 186W(n,γ)187W e 191Ir(n,γ)192Ir estudadas neste trabalho, em que todas as incertezas parciais envolvidas no processo foram utilizadas; a determinação experimental dos fatores de autoblindagem para nêutrons térmicos (Gth) e epitérmicos (Ge ) utilizados nas determinações de k0 e Q0 para a reação 113In(n,γ)114mIn e na determinação experimental do fator de autoblindagem para nêutrons epitérmicos (Ge ) utilizado na determinação de k0 e Q0 para a reação 186W(n,γ)187W, que não foram observadas na literatura, além da determinação de k0 obtida para a reação 186W(n,γ)187W na energia de 625,51 keV, que também não existe na literatura recomendada. Os valores de k0 e Q0 obtidos para todas as reações foram comparados aos valores encontrados na literatura.
Calibration of the short irradiation facility for k0 - NAA implementation at the IEA-R1 reactor
2021 - OLIVEIRA, J.P.; SILVA, P.S.C.; SEMMLER, R.; DIAS, M.S.; KOSKINAS, M.F.; MOREIRA, D.S.; YAMAZAKI, I.M.
The short irradiation facility of the IEA-R1 nuclear research reactor at IPEN, São Paulo, Brazil, has been used for short irradiation of samples for the purpose of determining the concentration of elements of these samples through the use of the instrumental neutron activation analysis technique. With the aim of determine precisely the reactor parameters α and f, for implementing the k0-NAA method at the Neutron Activation Analysis Laboratory (LAN), was used the bare triple method. In this method, a set of three neutron flux monitors were irradiated without Cd-cover. The efficiency curve of the gamma-ray spectrometer used was determined by measuring calibrated radioactive sources at the commonly used counting geometries. The results for the parameters α and f were respectively 0.0384±0.0016 and 35.67±0.26. This value of f shows that the neutrons in the irradiation position are well thermalized. The variation of these parameters was studied with time and the reproducibility was verified.
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.
Preliminary measurements of k0 values for W-186
2017 - BARROS, LIVIA F.; DIAS, MAURO S.; KOSKINAS, MARINA F.; YAMAZAKI, IONE M.; SEMMLER, RENATO
There are various methods of neutron activation analysis, one of these is the k0 Method for quantitative reactor Neutron Activation Analysis (NAA). The k0-NAA procedure is nowadays widely used in numerous laboratories performing NAA all over the world. Among these reactions, 186W(n, )187W can be considered important because it can be used for a W concentration measurements. The irradiations were performed at position 24A, near the core of the IEA-R1 4.5 MW swimming-pool nuclear research reactor of the Instituto de Pesquisas Energéticas e Nucleares (IPEN-CNEN/SP – Nuclear and Energy Research Institute), in São Paulo, Brazil. Two irradiations were carried out in sequence, using two sets of samples: the first with a cadmium cover around the samples and the second without, in a total of three data sets with and without Cd cover performed in 2014 and 2015. The activity measurements were carried out in an HPGe gamma-ray spectrometer. Standard sources of 152Eu, 133Ba, 60Co and 137Cs supplied by the IAEA were used in order to obtain the HPGe gamma-ray peak efficiency as a function of the energy. The covariance matrix methodology was applied to all uncertainties involved. The preliminary values of k0 for 186W(n, )187W reaction for the gamma transition energy of 479.53 keV was 3.17x10-2(5), for 618.77 keV was 9.08x10-3(15) and for 685.77 keV was 3.88x10-2(6). These preliminary values for k0 have been compared with the literature.
Measurement of doubly differential electron bremsstrahlung cross sections at the end point (tip) for C, Al, Te, Ta and Au
2017 - GARCIA-ALVAREZ, J.A.; FERNANDEZ-VAREA, J.M.; VANIN, V.R.; SANTOS, O.C.B.; BARROS, S.F.; MALAFRONTE, A.A.; RODRIGUES, C.L.; MARTINS, M.N.; KOSKINAS, M.F.; MAIDANA, N.L.
We have used the low-energy beam line of the São Paulo Microtron accelerator to study the maximum energy transfer point (tip) of electron–atom bremsstrahlung spectra for C, Al, Te, Ta and Au. Absolute cross sections differential in energy and angle of the emitted photon were measured for various electron kinetic energies between 20 and 100 keV, and photon emission angles of 35◦, 90◦ and 131◦. The bremsstrahlung spectra were collected with three HPGe detectors and their response functions were evaluated analytically. Rutherford backscattering spectrometry allowed us to obtain the thicknesses of the targets with good accuracy. We propose a simple model for the tip region of the bremsstrahlung spectrum emitted at a given angle, whose adjustable parameters are the mean energy of the incident beam and its spread as well as an amplitude. The model was fitted simultaneously to the pulse-height distributions recorded at the three angles, determining the doubly differential cross sections from the corresponding amplitudes. The measured values have uncertainties between 3% and 13%. The agreement of the experimental results with the theoretical partial-wave calculations of Pratt and co-workers depends on the analyzed element and angle but is generally satisfactory. In the case of Al and Au, the uncertainty attributed to the theory is probably overestimated.
Impurity determination in 153Sm by means of a High Purity Germanium spectrometer
2016 - ALMEIDA, JAMILLE da S.; KOSKINAS, MARINA F.; MARQUES, CAIO P.; MOREIRA, DENISE S.; DIAS, MAURO da S.
Neste trabalho, a impureza radionuclídica de longa duração 152Eu, presente na solução de 153Sm, foi medida por meio de um espectrômetro de HPGe, calibrado na faixa de energia entre 81 e 1408 keV por meio de soluções padronizadas em ampolas seladas de 60Co, 133Ba, 137Cs e 152Eu. A razão entre as atividades do 152Eu e do 153Sm resultou 5,2x10-6. Este valor é menor que o limite estabelecido pelo controle de qualidade.
Determination of k0 for 186W(n,gamma)187W, 94Zr(n,gamma)95Zr and 96Zr(n, gamma)97Zr reactions with covariance analysis
2015 - BARROS, LIVIA F.; DIAS, MAURO da S.; KOSKINAS, MARINA; YAMAZAKI, IONE; SEMMLER, RENATO
Determination of ksub(0) for sup(63)Cu(n,'gamma')sup(64)Cu reaction with covariance analysis
2015 - BARROS, LIVIA F.; DIAS, MAURO S.; KOSKINAS, MARINA F.; YAMAZAKI, IONE M.; SEMMLER, RENATO