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Graduado em Física pela Pontifícia Universidade Católica de São Paulo (1989), Mestre em Tecnologia Nuclear pela Universidade de São Paulo (1993) e Doutor em Tecnologia Nuclear pela Universidade de São Paulo (2006). Atualmente é pesquisador da Comissão Nacional de Energia Nuclear (CNEN), lotado no Centro do Reator de Pesquisas (CERPq) do Instituto de Pesquisas Energéticas e Nucleares (IPEN). Docente da pós-graduação stricto sensu - Programa de tecnologia nuclear do IPEN - Universidade de São Paulo e da pós-graduação stricto sensu - Mestrado profissional de tecnologia das radiações na saúde. Tem experiência na área de Física Nuclear de baixas energias atuando nos seguintes temas: reações de captura de nêutrons térmicos (prompt gamma rays), método k0 de análise por ativação neutrônica, caracterização do espectro de nêutrons junto aos canais de irradiação do reator IEA-R1, espectroscopia gama, fotodesintegração, reações fotonucleares (fotofissão e fotonêutrons) e ensino de física. Professor e organizador da EAEN - Escola Avançada de Energia Nuclear para estudantes do Ensino Médio, preferencialmente envolvidos com olimpíadas de física e química: Teoria e Aplicações das Ciências Nucleares. Professor de física com mais de 25 anos de experiência em cursos universitários, pré-vestibular e ensino médio. (Texto extraído do Currículo Lattes em 27 dez. 2021)

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Agora exibindo 1 - 4 de 4
  • Artigo IPEN-doc 27914
    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.
  • Artigo IPEN-doc 24065
    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.
  • Resumo IPEN-doc 21539
    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
  • Artigo IPEN-doc 21069
    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