MONISE BRITO GOMES

MONISE BRITO GOMES

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Study of the centers responsible for the TL emission by EPR and PL analysis of Eu-doped CaSiO3 phosphors synthesized by the devitrification method
2024 - GONZALES-LORENZO, CARLOS D.; GUNDU RAO, T.K.; CCOLLQUE-QUISPE, ALBERTO A.; AYALA-ARENAS, JORGE; GOMES, MONISE B.; SILVA-CARRERA, BETZABEL N.; GENNARI, ROSELI F.; PACHAS, VALERIA S.; MONZON-MACEDO, F.; LORO, H.; CHUBACI, JOSE F.D.; CANO, NILO F.; ROCCA, RENE R.; WATANABE, SHIGUEO
CaSiO3 doped at different ppm of Eu were synthesized by the devitrification method. Polycrystals exhibit a prominent high-temperature TL peak that increases in intensity and shifts toward higher temperatures with increasing amounts of dopant. TL emission spectrum of CaSiO3: Eu displays two very broad bands centered at 400 and 440 nm corresponding to the temperatures of 229.5 and 373.5 degrees C, respectively. PL measurements indicate the presence of Eu2+ and Eu3+ ions. EPR spectrum arises from two defect centers. One of the centers with principal g-values 2.016, 2.0091, and 2.0051 is attributed to O- ion and the center correlates with the TL peak at 236 degrees C. Center II with an isotropic g-value of 2.0018 is attributed to an F+ center and the center relates to the TL peak at 120 degrees C. Center III is also tentatively identified as the F+ center which is associated with the TL peak at 365 degrees C.
Luminescence dating and firing temperature determination of ancient ceramics fragments from the Tunata-hill site in the Churajon archaeological complex in Arequipa, Peru
2023 - PACOMPIA, YOLANDA; SUPO-RAMOS, JUSTO G.; GONZALES-LORENZO, CARLOS D.; CALLO-ESCOBAR, DARWIN J.; ROCCA, RENE R.; PASTRANA, ELIZABETH C.; GOMES, MONISE B.; SILVA-CARRERA, BETZABEL N.; WATANABE, S.; AYCA-GALLEGOS, OSCAR; AYALA-ARENAS, JORGE S.
Ancient pottery fragments from the Tunata-hill site in Churajon archaeological complex, Arequipa, Peru, were dated by means of luminescence techniques such as thermoluminescence (TL) and optically stimulated luminescence (OSL) in order to provide absolute chronology. For TL, additive and regenerative methods were performed. For OSL a regenerative method was carried out for IRSL dating. A rigorous description of the study area and its context has been made. The ages of the samples were found to be between 0.50 ± 0.06 ky and 0.49 ± 0.03 ky for TL methods, and 0.49 ± 0.02 ky for OSL methods. On average, the estimated age by TL and OSL techniques is 490 ± 70 yr (1600 AD and 1460 AD). This means that Churajon ceramics under study would belong to the Late periods which corresponds to the Inca region, and the North sub-region of the Late Churajon phase, and the beginning of European colonization in Peru. X-ray fluorescence technique (XRF) analysis has shown the main presence of Fe (39.5%), Si (30.0%), and Al (10.4%) in fine pottery powder. Furthermore, the electron paramagnetic resonance (EPR) technique was used to study the firing temperature using the iron signal (Fe3+) as a firing temperature reference. The firing temperature of ceramics was found to be around 550 ± 50 °C.
EPR dating of sediments in the region of Iguape - Cananéia, Brazil
2021 - CORTEZ, B.; CHUBACI, J.F.D.; GOMES, M.B.; MENDES, L.; ROCCA, R.R.; ARIZACA, E.C.E.; WATANABE, S.
Dating of sediments was performed by physics method in this work. Natural radioactivity is present in sediments, and this method is based on the measurement of energy of radiation stored in the solid. Gamma irradiation of sediments create deffects in quartz structure that stores energy by the absorption of radiation. In the present work, Icapara sediment dating was done by Electron Paramagnetic Resonance (EPR) spectroscopy method. The intensity of EPR signal corresponding to the number of lattice defects with an unpaired electron in sediment quartz could be measured to estimate the accumulated dose of natural radiation and to calculate the geologic age. Located in the region of Iguape at southeast coast of São Paulo State, Icapara is a large sand terrace that was formed due to sea level fluctation that occurred more than 130 thousand years ago. Samples were taken from a point about 9 - 10 meters above the current control of the sea. Ages of 38,000 ±12,000 and 46,000 ± 7,000 years were obtained in this study by EPR analysis that are correlated with the Quaternary Period.
Study of thermoluminescence of green quartz pellets for low dose dosimetry
2020 - CUEVAS-ARIZACA, E.E.; MAXIMO RONDON, R.; ROCCA, R.R.; GOMES, M.B.; CORTEZ, B.; GONZALES-LORENZO, C.D.; TAKARA, J.H.; GUNDU RAO, T.; CANO, N.F.; CHUBACI, J.F.D.; CAMPOS, L.L.; WATANABE, S.
Green quartz is usually studied for low dose TL dosimetry of gamma and X radiation. The aim of the present work is the dosimetric characterization of natural green quartz in the dose range of 0.47 mGy up to 1000 mGy of gamma and X radiation. Green quartz pellets were produced by cold pressing green quartz powder. The pellets are very sensitive to gamma and X radiation with main prominent TL peak at 230 °C. The TL sensitivity of MTS-N (LiF:Mg,Ti) and green quartz pellets were also compared. The dose response curve presented linear behavior in the dose range studied. The glow curve was deconvoluted. Kinetic parameters such as trap depth, kinetic order (b) and frequency factor (s) are determined. The TL photon energy dependence was also evaluated.
Datação de conchas e sedimentos correlacionados à flutuação do mar na região de Búzios, RJ
2020 - GOMES, MONISE B.
A formação da planície costeira brasileira deve-se principalmente à flutuação do nível relativo do oceano no passado. A Armação dos Búzios é um município da Microrregião dos Lagos, no estado do Rio de Janeiro. Seu limite oeste se estende à região de terras baixas, 2 m acima do atual nível do mar atual. Faz parte da planície do rio Una, uma região chamada de Pântano da Malhada e vestígio de conchas são encontradas nessa região. Nesse estudo, conchas e sedimentos foram coletados da região do Pântano da Malhada e datados, no caso dos cristais de quartzo extraídos dos sedimentos foram utilizadas as técnicas de Termoluminescência (TL) e Luminescência Opticamente Estimulada (LOE), e para as conchas foram utilizadas as técnicas de Ressonância Paramagnética Eletrônica (RPE) e datação por C-14. A taxa de dose anual (Dan) obtidas variou de 1,27 até 2,70 mGy/ano, os valores de dose acumulada (Dac) foram determinadas através do método de doses regenerativas para o LOE, utilizando o protocolo SAR "single-aliquot regenerative dose" e para TL e RPE as doses acumuladas foram determinadas através do protocolo MAAD "Multiple Aliquot Additive Dating". Os resultados das datações mostram idades entre 2480 e 5900 anos. As idades dos cristais de quartzo obtidas por LOE e TL são compatíveis e as idades das conchas obtidas por radiocarbono e RPE não estão compatíveis (foram realizados teste de compatibilidade nas respectivas comparações). Entretanto, alguns fatores podem influenciar na comparação das duas técnicas, como a quantidade de amostra; outro fator que pode afetar as idades obtidas das conchas no caso do método RPE é o teor de água. Como a água é um agente atenuante, a presença de água no local onde estavam as conchas poderiam proteger a concha da irradiação externa dos sedimentos ao redor. Apesar disso, todos os resultados obtidos referem-se às idades do período holocênico. Esse trabalho corrobora com a hipótese da presença natural das conchas, onde no passado houve uma transgressão do mar na região do Pântano da Malhada e com o passar do tempo o mar regrediu deixando na região vestígios de conchas de moluscos.
Thermoluminescence studies of polycrystalline CaSiO3 pellets for photons and particle therapy beams
2020 - GONZALES-LORENZO, CARLOS D.; NASCIMENTO, LUANA F.; KODAIRA, SATOSHI; GOMES, MONISE B.; WATANABE, SHIGUEO
In this work, pellets of CaSiO3 have been produced for investigation as gamma radiation, proton, and carbon ions detector. They were then irradiated to gamma radiation using 137Cs and 60Co sources. Furthermore, pellets of CaSiO3 were exposed to 160 MeV proton and 290 MeV/n carbon ion beam from an upper synchrotron. Thermoluminescence (TL) responses of these pellets presented the same prominent peak at about 170 °C, and two possible high-temperature peaks at 270 and 320 °C when irradiated to gamma, proton, and carbon ion beam. Dose-response curve, minimum detectable dose (MDD), energy dependence, and dependence on the dose rate when irradiated with gamma radiation were evaluated in this material. Linear dose-response curves for proton and carbon ion irradiation have been compared to that of the gamma dose-response. In this way, the dose read out in Harshaw TL reader presented a good agreement with doses found using ion chamber in the case of proton beams and slightly less in the case of carbon beam due to the LET dependency. Furthermore, relative efficiencies of CaSiO3 for beam irradiation of proton and carbon ion display no dependence in the analyzed particle doses range.
EPR dating of shells from Malhada Marsh, Rio de Janeiro, Brazil
2020 - GOMES, M.B.; OLIVEIRA, L.M.; CORTEZ, B.; D'OCA, M.C.; TRANCHINA, L.; TOMARCHIO, E.; PARLATO, A.; CHUBACI, J.F.D.; GENNARI, R.; ROCCA, R.R.; D'ERRICO, F.; SOUSA, S.; WATANABE, S.; MARRALE, M.
The formation of the coastal plain of the Brazilian sea is mainly due to the fl uctuation of relative sea level in the past. Armação dos Buzios or simply Buzios is a municipality in the microregion of lakes, in the state of Rio de Janeiro. In this region there is a lowland area about two meters above current sea level. This lowland area is also known as coastal plain of Una River. It is expected that during the Holocene period the sea level reached a maximum about 2.5 meters above the current level. During that time billions of mollusks lived and proliferated in the shallow waters around the coastal plain of the Una River. As they died their shells formed a layer in the soil including Malhada Marsh that belongs to the Una River plain. In this study, shells were collected from this region and dated using the techniques of Electronic Paramagnetic Resonance (EPR). Ages from 2480±130 to 4490±270 years were obtained. Radiocarbon dating were performed at the Beta Analytic Lab, USA for comparison with the EPR results. Shells ages obtained are compatible with geological data from the Holocene period relative to past sea level fl uctuations.
Electron Spin Resonance and Thermoluminescence dating of shells and sediments from Sambaqui (shell mound) Santa Marta II, Brazil
2020 - OLIVEIRA, L.M.; GOMES, M.B.; CORTEZ, B.; D'OCA, M.C.; TRANCHINA, L.; TOMARCHIO, E.; PARLATO, A.; CHUBACI, J.F.D.; GENNARI, R.; ROCCA, R.R.; D'ERRICO, F.; SOUSA, S.; WATANABE, S.; MARRALE, M.
In Tupi, the word Sambaqui means “mound of shells”. These archaeological sites are cultural vestiges left by the prehistoric occupation of the Brazilian coast from fi ve to six thousand years ago. Mollusks, fi shes, and other marine edible foods were important for the survival of this population. The remains of foods, mainly shells, were heaped up, giving a mound of different proportions, which became part of the landscape of the Brazilian coastal plain. Due to the large number of Sambaquis in Brazil and considering that Sambaqui Santa Marta II, Laguna, SC, has not yet been dated, Electron Spin Resonance (ESR) measurements were performed in aragonite shells collected from different layers of Sambaqui Santa Marta II, starting from the base to the center of the Sambaqui. Radiocarbon analysis by Accelerator Mass Spectrometry (AMS) at Beta Analytic laboratory were also performed for comparison with ESR results. Before measurements, shells were chemically etched, after drying, were pulverized and sieved. The sediments were separated into small portions which were irradiated with gamma radiation from a 60Co source with doses from 5 up to 120 Gy. Ages around 2,000 to 4,000 years have been obtained. The results obtained are consistent with the dates of others Sambaquis of the region, possibly were built at the same time.
Dating sediments from a terrace found in Iguape - Icapara in southeast coast in the state of São Paulo, Brazil
2018 - CORTEZ, BRUNA; CHUBACI, JOSE F.D.; GOMES, MONISE B.; OLIVEIRA, LETICIA M.; SATIRO, LUCAS C.; ROCCA, RENE R.; ARIZACA, EDY E.C.; WATANABE, SHIGUEO
Dating of shells from Pântano da Malhada, Rio de Janeiro
2018 - GOMES, MONISE B.; CORTEZ, BRUNA; OLIVEIRA, LETICIA M. de; CARMO, LUCAS S. do; CHUBACI, JOSE F.D.; ROCCA, RENE R.; WATANABE, SHIGUEO

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