CLAUDIO DOMIENIKAN
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Resumo IPEN-doc 26847 A compact electronic system for a photodiode neutron detector2019 - COSTA, PRISCILA; RAELE, MARCUS P.; DOMIENIKAN, CLAUDIO; COSTA, FABIO E.; MADI FILHO, TUFIC; ZAHN, GUILHERME S.; GENEZINI, FREDERICO A.The demand for portable neutron detectors is on the rise, and for that purpose, low cost boron-10 has been frequently used instead of helium-3, which is usually employed in large and expensive detectors. Portable detectors are of interest in some applications, such as neutron dosimeters or inspection systems targeted in the detection of fissile material and drugs in airports. In this work a portable thermal neutron detection system was developed which is based on a commercial silicon photodiode coupled to a boron converter; this prototype is then plugged into a portable electronic system. The boron layer was produced by pulsed laser deposition, either on a thin glass slide or on the photodiode itself. The boron deposition in the photodiode was made directly in the active area of the detector, so before and after the deposition process a characterization of the device regarding both the dark current and the operation voltage was performed using an americium source. Finally, both configurations were tested. The neutron detection process occurs by detecting the alpha and lithium particles produced by the interaction of the incoming neutron with the boron-10 nuclides. These heavy ions then interact with the active area of the reverse-biased photodiode, producing an electric signal that has to be preamplified and then properly amplified by the portable electronic system, which in turn produces an output that can either be sent to a multichannel analyzer or to a digital counter. The integrated circuit of the low noise preamplifier transforms the detector’s current pulse into a voltage pulse with amplitude proportional to the charge carried by the current pulse. The shaper-driver consists of a differentiator and an integrator and is responsible for filtering and further amplifying the preamplifier signal, generating a NIM-compatible energy output pulse. The performance of the photodiode-amplifier set for alpha particles was successively tested using a 243Am radioactive source. Initial tests were made using the boron-deposited glass, and the electronic signal was properly read. However, when the same system was tested using the boron deposited directly in the photodiode, the output signal couldn’t be read, due to the fact that during the deposition process there was an increase in the dark current and a decrease in the operation bias. In this way, a new portable electronic system was developed using a hybrid integrated amplifier circuit. This new electronic setup allowed the use of both configurations, and was tested both with alpha-emitting Americium and neutron-emitting AmBe sources. In conclusion, both portable electronic systems have proven suitable for the thermal neutron detector developed.Artigo IPEN-doc 26204 Characterization of a portable thermal neutron detector2019 - COSTA, PRISCILA; RAELE, MARCUS P.; DOMIENIKAN, CLAUDIO; MADI FILHO, TUFIC; ZAHN, GUILHERME S.; GENEZINI, FREDERICO A.A portable thermal neutron detector prototype, using a PIN-type silicon photodiode coupled to a boron converter, was developed at the Nuclear and Energy Research Institute (IPEN-CNEN/SP). Several boron layers were made by Pulsed Laser Deposition method and two different prototypes were made using distinct approaches in the associated electronics. The prototypes were characterized by measurements with the cold neutron beam at PHADES (Polarized 3He and Detector Experiment Station), in the NIST Center for Neutron Research. The distance between the prototype and the neutron source was different for each prototype: 70 cm (prototype one) and 7 cm (prototype two). The linearity behavior was verified for both prototypes in order to verify the relationship between counts and neutron fluence. The intrinsic efficiency values obtained for prototypes one and two were, respectively, (1.78 ± 0.01)% and (5.2 ± 0.4)%. The angular dependence was verified only for prototype one. The concept of this detector can be applied in a future dosimeter project.Artigo IPEN-doc 24325 Anomalous behavior of the magnetic hyperfine field at 140Ce impurities at La sites in LaMnSi22018 - DOMIENIKAN, C.; BOSCH-SANTOS, B.; CABRERA-PASCA, G.A.; SAXENA, R.N.; CARBONARI, A.W.Magnetic hyperfine field has been measured in the orthorhombic intermetallic compound LaMnSi2 with perturbed angular correlation (PAC) spectroscopy using radioactive 140La(140Ce) nuclear probes. Magnetization measurements were also carried out in this compound with MPSM-SQUID magnetometer. Samples of LaMnSi2 compound were prepared by arc melting the component metals with high purity under argon atmosphere followed by annealing at 1000°C for 60 h under helium atmosphere and quenching in water. X-ray analysis confirmed the samples to be in a single phase with correct crystal structure expected for LaMnSi2 compound. The radioactive 140La (T1/2 = 40 h) nuclei were produced by direct irradiation of the sample with neutrons in the IEA-R1 nuclear research reactor at IPEN with a flux of ∼ 1013 n cm−2s−1 for about 3 - 4 min. The PAC measurements were carried out with a six BaF2 detector spectrometer at several temperatures between 10 K and 400 K. Temperature dependence of the hyperfine field, Bhf was found to be anomalous. A modified two-state model explained this anomalous behavior where the effective magnetic hyperfine field at 140Ce is believed to have two contributions, one from the unstable localized spins at Ce impurities and another from the magnetic Mn atoms of the host. The competition of these two contributions explains the anomalous behavior observed for the temperature dependence of the magnetic hyperfine field at 140Ce. The ferromagnetic transition temperature (TC) of LaMnSi2 was determined to be 400(1) K confirming the magnetic measurements.Artigo IPEN-doc 24095 Low-cost amplifier for alpha detection with photodiode2017 - DOMIENIKAN, CLAUDIO; COSTA, PRISCILA; GENEZINI, FREDERICO A.; ZAHN, GUILHERME S.A low-cost amplifier for Hamamatsu S3590-09 PIN photodiode to be used in alfa detection is presented. This amplifier consists basically of two circuits: a pulse preamplifier and a shaper-driver. The PIN photodiode is reverse-biased and connected to a charge preamplifier input. Incident alpha particles generate a small current pulse in the photodiode. The integrating circuit of the low noise preamplifier transforms current pulse into a voltage pulse with amplitude proportional to the charge carried by the current pulse. The shaper-driver consists of a differentiator and an integrator and is responsible for filtering and further amplifying the preamplifier signal, generating a NIM-compatible energy pulse. The performance of the set photodiode-amplifier was successively tested through the use of a 243Am radioactive source. The low-cost photodiode amplifier was designed and constructed at IPEN - CNEN/SP using national components and expertise.Resumo IPEN-doc 23305 Hyperfine field at La in the intermetallic compound LaMnSi2 measured by PAC using 140Ce nuclear probe2016 - DOMIENIKAN, CLAUDIO; BOSCH-SANTOS, BRIANNA; PASCA, GABRIEL A.C.; SAXENA, RAJENDRA; CARBONARI, ARTURMagnetic hyperfine field has been measured in the orthorhombic intermetallic compound LaMnSi2 with PAC spectroscopy using radioactive 140La-140Ce nuclear probes. Magnetization measurement was also carried out in this compound with MPSM-SQUID magnetometer. The LaMnSi2 sample was prepared by melting pure metallic components in stoichiometric proportions in an arc furnace under argon atmosphere. After melting, the sample was annealed at 1000 o C for 60h under helium atmosphere and then quenched in to water. X-ray analysis confirmed the sample to be in a single phase with correct crystal structure expected for LaMnSi2. The radioactive nuclei, 140La (T1/2 = 40h) were produced by direct irradiation of the sample with neutrons in the IEA-R1 nuclear research reactor at IPEN with a flux of ~1013 ncm-2s-1 for about 3-4 min. The irradiated sample was annealed at 1000 o C under helium atmosphere for 24 hours before starting the PAC measurement in order to minimize the effects of eventual radiation damage by fast neutrons during irradiation as well as to allow the decay of the short lived 56Mn (T1/2 = 2.6h) activity also produced in the sample. The PAC measurements were carried out with a six BaF2 detector spectrometer at several temperatures between 10 K and 400 K. The results showed well defined magnetic dipole interaction at all temperatures. Temperature dependence of the hyperfine field, Bhf was found to be anomalous. The magnetization measurement however, showed no anomaly. Therefore, the anomalous behavior of Bhf may be attributed to the interaction where 1f electron of the dilute Ce atom is spin polarized by the magnetic field from Mn sublattice and contributes to the effective hyperfine field. The ferromagnetic transition temperature (TC) of LaMnSi2 was determined to be 400(1) K confirming by magnetic measurement and the earlier results.Tese IPEN-doc 22026 Desenvolvimento de um espectrômetro de correlação angular gama-gama perturbada com seis detectores de BaF2 e estudo de interações hiperfinas em composto intermetálico LaMnSi22016 - DOMIENIKAN, CLAUDIONeste trabalho foi desenvolvido um Espectrômetro de Correlação Angular Gama- Gama Perturbada Diferencial em Tempo (CAP) constituído por seis detectores cintiladores de BaF2, para realização de medidas de interações hiperfinas (campo hiperfino magnético e gradiente de campo elétrico) em diversos materiais e propiciar estudos na área da física da matéria condensada. O espectrômetro desenvolvido possui um sistema de aquisição não convencional em comparação aos demais equipamentos destinados a medidas de CAP. Ao invés do tradicional Analisador Multicanal (MCA), este espectrômetro utiliza um sistema de aquisição de dados constituído, basicamente, por um Conversor Analógico Digital (ADC) rápido, uma placa digital (I/O) convencional e um roteador construído no laboratório de Interações Hiperfinas (LIH) do IPEN. Este versátil e eficiente sistema, controlado por um software também criado no LIH em LabVIEW, permite a geração simultânea de 30 espectros de coincidências γ - γ atrasadas, número superior em comparação aos 12 espectros do antigo espectrômetro de quatro detectores. Além de medidas de linearidade, resolução em tempo e tempo morto, o funcionamento e o desempenho do espectrômetro foram comprovados através de medidas de CAP utilizando os núcleos de prova 111In -> 111Cd e 181Hf -> 181Ta, cujos resultados são bem conhecidos da literatura. Foram feitas medidas de interação quadrupolar do 181Ta em háfnio metálico e do 111Cd em cádmio metálico, e de campo hiperfino magnético do 111Cd e do 181Ta em níquel. Os resultados destas medidas se mostraram em concordância com a literatura. Adicionalmente foram realizadas medidas inéditas de interações hiperfinas magnéticas no composto intermetálico LaMnSi2 utilizando os núcleos de prova 111Cd e 140Ce. As medidas foram realizadas na faixa de temperatura de 10 K a 400K. No caso das medidas utilizando a sonda 111In -> 111Cd, os resultados mostram uma variação do campo magnético com a temperatura que segue a função de Brillouin. Já no caso das medidas com o núcleo de prova 140La -> 140Ce, o resultado apresentou um comportamento anômalo do campo hiperfino em função de temperatura. Os resultados evidenciam uma forte hibridização da banda 4f do Ce com a banda 3d do Mn, fato verificado e estudado em trabalhos anteriores com compostos semelhantes.Resumo IPEN-doc 22330 Hyperfine field at Mn in the intermetallic compound LaMnSi2 measured by PAC using sup(111)Cd nuclear probe2014 - DOMIENIKAN, CLAUDIO; SANTOS, BRIANNA B.; CABRERA PASCA, GABRIEL A.; SAXENA, RAJENDRA N.; CARBONARI, ARTUR W.Artigo IPEN-doc 20793 Hyperfine field at Mn in the intermetallic compound LaMnSisub(2) measured by PAC using sup(111)Cd nuclear probe2015 - DOMIENIKAN, C.; BOSCH-SANTOS, B.; CABRERA PASCA, G.A.; SAXENA, R.N.; CARBONARI, A.W.Artigo IPEN-doc 20649 The new facility for neutron tomography of IPEN-CNEN/SP and its potential to investigate hydrogenous substances2014 - SCHOUERI, R.M.; DOMIENIKAN, C.; TOLEDO, F. de; ANDRADE, M.L.G.; STANOJEV PEREIRA, M.A.; PUGLIESI, R.Resumo IPEN-doc 09234 Routing interface for multidetector angular correlation spectrometer2003 - DOMIENIKAN, C.; GENEZINI, F.A.; ZAHN, G.S.; MEDEIROS, J.A.G.; CRUZ, M.T.F.
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