Oceanic anoxic events (OAEs) are periods in Earth's history when oceans were depleted in dissolved oxygen and characterized by deposition of organic-rich sediments. The Oceanic Drilling Program (ODP) has drilled through OAEs in a number of areas worldwide, collecting core and borehole log data. This project attempts to identify a characteristic signature from known ODP OAE sections using these data and to apply the signature to identify OAE intervals in Gulf of Mexico wells where cores are lacking. Additionally, pseudo density curves were generated from ODP logs and compared to bulk density logs to determine if the deviation between the two would aid identification of OAE intervals. A general, though not fool proof, signature of high gamma ray, uranium, neutron porosity and low density was seen in nearly all of the ODP holes. Using this signature 20 potential OAE intervals were identified in the Gulf of Mexico.

Cette thèse présente les résultats de la recherche de signaux impulsionnels d’ondes gravitationnelles associés aux sursauts gamma dans les données 2009-2010 des interféromètres LIGO-Virgo. L’étude approfondie des mécanismesd’émission d’ondes gravitationnelles par les progéniteurs de sursauts gamma, ainsi que des mécanismes d’émission de rayons gamma eux-mêmes, permet de déterminer les caractéristiques essentielles du signal à détecter : polarisation, délai temporel, etc ... Cette connaissance de l’émission conjointe permet alors de construire une méthode d’analyse qui inclut les a priori astrophysiques. Cette méthode est de plus robuste vis-à-vis des bruits transitoires présents dans les données. L’absence de détection nous permet de placer des limites observationnelles inédites sur la population des sursauts gamma. / In this thesis we present the results of the search for gravitational wave bursts associated with gamma-ray bursts in the 2009-2010 data from the LIGOVirgo gravitational wave interferometer network. The study of gamma-ray bursts progenitors, both from the gamma-ray emission and the gravitational wave emission point of view, yields the characteristic of the sought signal: polarization, time delays, etc ... This knowledge allows the construction of a data analysis method which includes the astrophysical priors on joint gravitational wave and gamma-ray emission, and moreover which is robust to non-stationary transient noises, which are present in the data. The lack of detection in the analyzed data yields novel observational limits on the gamma-ray burst population.

Cette thèse porte sur la conception et la réalisation du système optique d'une nouvelle source de rayonnement gamma, ELI-NP-GBS (Extreme Light Infrastructure - Nuclear Physics - Gamma Beam Source), qui utilise des développements récents des technologies des lasers, de l'optique et des accélérateurs. Les caractéristiques finales que devra atteindre cette source sont au moins d'un ordre de grandeur, en intensité, supérieur à la meilleure machine Compton actuelle, HIGS. Un nouveau type de système optique a été conçu pour ELI-NP-GBS. Il s'agit d'un système à 32 passages composé de deux miroirs paraboliques confocaux et d'un ensemble de paires de miroirs. Les miroirs paraboliques permettent la focalisation et la collimation successives d'un faisceau laser de haute intensité (400 mJ par impulsion). La géométrie "dragon-shape" garantie que le croisement du faisceau laser avec le faisceau d'électron se produise avec un angle constant en un point unique. De telles performances sont assurées par un alignement des éléments optiques à mieux que quelques micromètres en position et quelques microradians en orientation et une synchronisation de tous les passages avec les paquets d'électrons à mieux que quelques centaines de femtosecondes. Cet alignement et cette synchronisation est obtenue par l'intermédiaire de procédures et d'algorithmes spécialement développés pour ce système. Les algorithmes ont ainsi été développés et testés sur des simulations numériques dédiées prenant en compte les aspects mécaniques et optiques du système tel que les pré-alignements mécaniques, les états de surfaces des miroirs, la polarisation du faisceau laser, etc. Une première preuve de principe de la méthode de synchronisation a été concluante. / This thesis is about the design and the realization of the optical system of a new gamma-ray source, ELI-NP-GBS (Extreme Light Infrastructure - Nuclear Physics - Gamma Beam Source), which benefits from the recent developments in laser technology, optics and accelerators. The final characteristics that this source aims to reach is one order of magnitude higher in intensity than the actual best Compton machine, HIGS. A new type of optical system has been designed for ELI-NP-GBS. It is a 32 passes system made of two confocal parabolic mirrors and a set of Mirror-Pair Systems. The parabolic reflectors focalize and collimate successively a high intensity laser beam (400 mJ per pulse). The ``dragon-shape'' geometry ensures that the laser beam and electron bunches cross at a constant angle in a unique point. These performances are guaranteed by a few micrometers precision in position alignment, a few microradians precision in orientation alignment and by a few hundreds femtoseconds synchronization between electron bunches and laser pulses for each pass. This alignment and this synchronization is performed by used of dedicated procedures and algorithms. These algorithms have been developed and tested with numerical simulations which take into account the mechanical and optical aspects of the system such as the mechanical pre-alignment, the mirrors' surface deformations, the laser beam polarization, etc. A first proof of principle of the synchronization method has been successful.

Neste trabalho são apresentados os resultados obtidos do estudo da estrutura do núcleo \'ANTPOT. 58 CO\' utilizando a técnica de espectroscopia de raios gama em linha. Este núcleo foi produzido a partir da reação de fusão-evaporação \'ANTPOT. 51 V\'(ANTPOT. 10 B\', p2n), com energia de feixe de 33 MeV incidindo em três alvos de 200\'mü\'g/\'cm POT. 2\', realizada no acelerador Pelletron da Universidade de São Paulo. Foram feitas medidas em coincidência \'gama\'\'gama\'-partícula com o espectrômetro de raios \'gama\' Saci-Pererê, composto de 4 detectores de GeHP com blindagem Compton, e um sistema auxiliar para detectar partículas carregadas, consistindo de 11 telescópios cintiladores \'delta\'E-E tipo phoswich. Foram encontradas quarenta e sete transições novas que depopulam trinta e sete novos estados. O esquema de níveis proposto foi estendido até uma energia de excitação de 8 MeV e momento angular de \'J POT. pi\'=\'11 POT. +\'. A atribuição dos valores de spins foi baseada na razão DCO (Correlação Direcional de Estados Orientados). Os resultados experimentais foram comparados com os calculados pelo Modelo de Camadas em Larga Escala (LSSM) utilizando os códigos MSHELL e Antoine, assim como a interação residual GXPF1, desenvolvida para ser usada na camada pf Foram interpretados dezenove estados excitados a partir do LSSM. Foram medidas também as vidas médias para treze estados excitados do \'ANTPOT. 58 CO\' utilizando o Método de Deslocamento Doppler Atenuado (DSAM). Para este estudo, o núcleo \'ANTPOT. 58 CO\' foi produzido a partir da reação \'ANTPOT. 51 V\'(ANTPOT. 10 B\', p2n) com energia de feixe de 36 MeV, usando um alvo de 770\'mü\'g/\'cm POT. 2\' prensado em um suporte de Pb. Os valores experimentais também foram comparados aos cálculos do LSSM. Probabilidades de transição reduzidas B(Ml), e portanto as vidas médias, foram bem reproduzidas pelo modelo teórico para cinco níveis identificados. Os níveis de energia observados apresentaram funções de onda com grande mistura de configurações sendo a principal dada por \'pi\'\'f POT -1 IND. 7/2\' (PRODUTO VETORIAL) v \'p POT 2 IND. 3/2\' \'f POT 1 IND. 5/2\',. Os resultados indicam que a maior parte dos estados excitados do núcleo \'ANTPOT. 58 CO\' tem um comportamento esférico e são bem reproduzidos considerando excitações de partícula única / The excited states in the doubly odd nucleus \'ANTPOT. 58 CO\' have been studied using inbeam gama-ray spectroscopy. The \'ANTPOT. 58 CO\' nucleus has been produced with the fusionevaporation reaction \'ANTPOT. 51 V\'(ANTPOT. 10 B\', p2n) at 33 MeV bombarding energy, using the SMV Pelletron accelerator of the University of São Paulo. Gamrna-gamma-charged particle coincidences were measured with the Saci-Pererê gama-ray spectrometer composed of 4 Compton-suppressed GeHP and an ancillary charged-particle detector system composed of 11 plastic phoswich scintillator ~E-E telescopes. We have found 47 new gama-transitions de-populating 37 new excited states. A level scheme extending up to an excitation energy of about 8.0 MeV and spin \'J POT. pi\'=\'11 POT. +\' has been proposed. The spin assignments were based on the DCO (Directional Correlation from Oriented States) ratios. The experimental results were compared with Large Scale Shell Model (LSSM) calculations performed with the MSHELL and Antoine codes using the GXPFl effective interaction, developed for use in the pf shell. We have interpreted 19 excited states in the frame of the LSSM. We have measured also the lifetimes for 13 excited states of the \'ANTPOT. 58 CO\' nucleus. The lifetimes were measured with the Doppler Shift Attenuation Method (DSAM). For this study the \'ANTPOT. 58 CO\' nuclei were populated with the reaction \'ANTPOT. 51 V\'(ANTPOT. 10 B\', p2n) at 36 MeV bombarding energy, using a target consisting of a 770\'mü\'g/\'cm POT. 2\' foil with Pb backing. The experimental values were also compared with the LSSM calculations. Experimental B(M1) reduced transition probabilities, and thus the lifetimes, are well reproduced by the theoretical model for fi v e o f the identified levels. The observed levels presented wave functions with large configuration mixing with the main configuration being \'pi\'\'f POT -1 IND. 1/2\' (PRODUTO VETORIAL) v \'p POT 2 IND. 3/2\' \'f POT 1 IND. 5/2\',. The results indicate that most of the excited states in the \'ANTPOT. 58 CO\' nucleus has a spherical behavior and is well reproduced considering single-particle excitations.

O método nuclear gamaespectrométrico vem ganhando espaço em diversas aplicações como fornecer a informação médica em um paciente ou de uma galáxia distante, detectar radioatividade para fins de segurança e medir a concentração de radioelementos em um mineral ou rocha. Esta dissertação apresenta um projeto e implementação de um espectrômetro gama digital conectado a um conjunto detector contendo cristal cintilador de iodeto de sódio dopado com tálio. O hardware é baseado em um dispositivo lógico programável da família CoolRunner II da Xilinx e um conversor analógico-digital de 80 MHz da Analog Devices. A aquisição de dados é executada em um computador pessoal comum. As linguagens de programação utilizadas foram VHDL e C#. O objetivo desta dissertação é apresentar todas as etapas necessárias para o desenvolvimento de um gamaespectrômetro digital e inclui pesquisa bibliográfica, estudo do equipamento, modelagem dos cristais, simulação do projeto de um gamaespectrômetro, montagem do circuito eletrônico, desenvolvimento do processamento e lógica do circuito, criação do software de aquisição dos dados em tempo real e apresentação dos resultados obtidos. / The gammaspectrometric method has been used for diverse applications as to supply the medical information in a patient or a distant galaxy, to detect radioactivity at airport and to measure the concentration of radioelements in a mineral or rock. This work presents a digital gammaspectrometer project and implementation for acquisition of radiometric data, the spectrometer is connected to a gamma-ray detector NaI(Tl). The two main components in hardware are complex programmable logical device of the family CoolRunner II Xilinx and an 80 MHz analog to digital converter of brand Analog Devices. The acquisition of data is executed in a common personal computer. The programming languages used are VHDL and C#. The objective of this work is to present all the needful stages for the digital gammaspectrometry development that includes theorem, equipment studying, crystal modeling, gammaspectrometry modeling and simulation, electronic circuit assembly, processing and logic circuit development, data acquisition software in real time development and presentation of results.

Kwong Lop Sam. / Thesis (M.Phil.)--Chinese University of Hong Kong. / Bibliography: leaves 60-63.

O presente trabalho teve como objetivo a padronização em atividade do radionuclídeo 177Lu, um importante radiofármaco utilizado no tratamento de câncer neuroendócrino. Este radionuclídeo se desintegra por emissão beta acompanhada de várias emissões gama simultâneas, o que tornou possível a aplicação do método de coincidência 4πβ-γ. Para a detecção da radiação beta, foi utilizado um detector proporcional (PC), com geometria 4π e dois cintiladores de NaI(Tl) para a detecção da radiação gama. Os sinais gerados nos detectores passaram por amplificadores, discriminadores e módulos atrasadores, para serem enviados a um analisador multicanal. Para este experimento, foi utilizado um sistema de coincidências que aplica um módulo TAC (Time to Amplitude Converter), o qual converte diferença de tempo em amplitude de pulso. Para obter-se a variação na eficiência beta, foram acrescentados absorvedores de Collodion nas partes superior e inferior da fonte radioativa. Desta forma, foi possível extrapolar o valor para eficiência beta igual a 100%, obtendo assim a atividade da fonte radioativa. A curva de extrapolação experimental foi comparada com a previsão teórica, obtida por meio do método de Monte Carlo. Além da padronização em atividade do 177Lu, também foram determinadas as suas probabilidades de emissão gama por decaimento para cada uma das principais transições gama, por meio de um espectrômetro de HPGe, previamente calibrado. / The present work aimed the activity standardization of radionuclide 177Lu, an important radioisotope used for treatment of neuroendocrine cancer. This radionuclide disintegrates by beta decay followed by several simultaneous gamma-ray emissions, which made possible the application of the 4πβ-γ coincidence method. For the detection of beta radiation in 4π geometry a proportional detector (PC) was used, and for gamma radiation detection a pair of NaI(Tl) scintillators was used. The signals generated by the detectors passed through amplifiers, discriminators and delay modules, and were sent to a multichannel analyzer. For the present experiment, the system includes a TAC (Time to Amplitude Converter) module which converts the time difference in pulse amplitude. To obtain the variation in beta efficiency, Collodion absorbers at the top and bottom of the radioactive source were applied. In this way, it was possible to extrapolate the beta efficiency value to 100%, thereby obtaining the radioactive source activity. The extrapolated experimental curve was compared with the theoretical prediction, obtained by means of the Monte Carlo method. Besides the activity standardization of 177Lu, its gamma-ray emission probabilities per decay for the main gamma transitions were also determined by means of an HPGe spectrometer, previously calibrated.

Studying nuclei beyond the proton dripline can provide valuable information on the structure of nuclei at the limits of stability, where the strong nuclear force starts to be overcome by Coulomb repulsion between protons. Simple experimental observables, such as excitation energies and lifetimes of excited states in these proton-unbound nuclei can provide information on the nuclear wave function. Experimental data, such as that presented in this work, can then be used to improve models of nuclear structure at the proton dripline. This thesis presents data from a recoil-decay tagged differential plunger experiment undertaken at the University of Jyvaskyla in 2014. A fusion-evaporation reaction was used to populate excited states in the deformed ground-state proton emitter 113Cs. The JUROGAM-RITU-GREAT experimental setup was used to correlate gamma rays emitted from these excited states with protons emitted from 113Cs and the differential plunger for unbound nuclear states (DPUNS) was placed at the target position to measure the excited state lifetimes. The lifetime of the (11/2+) state in the most intense rotational band of 113Cs was measured to be tau = 24(6) ps, while a limit of tau is less than or equal to 5 ps was found for the lifetime of the higher energy (15/2+) state. The lifetime of proton emission was measured to be tau = 24.2(2) microseconds. The experimental data were used to test the predictions of a non adiabatic quasi-particle model for proton-emitting nuclei, which was employed to deduce the deformation of the states in 113Cs. Wave functions from the non adiabatic quasi-particle model were used to independently calculate proton-emission rates, gamma-ray transition rates and excited state energies as functions of deformation. The deformation of 113Cs could then be extracted from the intersection of the different theoretical values and experimental observables. A deformation of beta2 = 0.22(6)was extracted from the (11/2+) excitation energy and lifetime. The deformation values taken from the proton-emission rate and the lifetime limit of the (15/2+) state were also consistent with this value. The consistency of the different deformations calculated shows the effectiveness of the non adiabatic quasi-particle method when used to calculate the properties of deformed ground-state proton-emitters.

O presente trabalho teve como objetivo a padronização em atividade do radionuclídeo 177Lu, um importante radiofármaco utilizado no tratamento de câncer neuroendócrino. Este radionuclídeo se desintegra por emissão beta acompanhada de várias emissões gama simultâneas, o que tornou possível a aplicação do método de coincidência 4πβ-γ. Para a detecção da radiação beta, foi utilizado um detector proporcional (PC), com geometria 4π e dois cintiladores de NaI(Tl) para a detecção da radiação gama. Os sinais gerados nos detectores passaram por amplificadores, discriminadores e módulos atrasadores, para serem enviados a um analisador multicanal. Para este experimento, foi utilizado um sistema de coincidências que aplica um módulo TAC (Time to Amplitude Converter), o qual converte diferença de tempo em amplitude de pulso. Para obter-se a variação na eficiência beta, foram acrescentados absorvedores de Collodion nas partes superior e inferior da fonte radioativa. Desta forma, foi possível extrapolar o valor para eficiência beta igual a 100%, obtendo assim a atividade da fonte radioativa. A curva de extrapolação experimental foi comparada com a previsão teórica, obtida por meio do método de Monte Carlo. Além da padronização em atividade do 177Lu, também foram determinadas as suas probabilidades de emissão gama por decaimento para cada uma das principais transições gama, por meio de um espectrômetro de HPGe, previamente calibrado. / The present work aimed the activity standardization of radionuclide 177Lu, an important radioisotope used for treatment of neuroendocrine cancer. This radionuclide disintegrates by beta decay followed by several simultaneous gamma-ray emissions, which made possible the application of the 4πβ-γ coincidence method. For the detection of beta radiation in 4π geometry a proportional detector (PC) was used, and for gamma radiation detection a pair of NaI(Tl) scintillators was used. The signals generated by the detectors passed through amplifiers, discriminators and delay modules, and were sent to a multichannel analyzer. For the present experiment, the system includes a TAC (Time to Amplitude Converter) module which converts the time difference in pulse amplitude. To obtain the variation in beta efficiency, Collodion absorbers at the top and bottom of the radioactive source were applied. In this way, it was possible to extrapolate the beta efficiency value to 100%, thereby obtaining the radioactive source activity. The extrapolated experimental curve was compared with the theoretical prediction, obtained by means of the Monte Carlo method. Besides the activity standardization of 177Lu, its gamma-ray emission probabilities per decay for the main gamma transitions were also determined by means of an HPGe spectrometer, previously calibrated.

Orientador: Hirasilva Borba Alves de Soza / Banca: Vera Fernanda Martins Hossepian de Lima / Banca: Maria Regina Barbieri de Carvalho / Banca: Alexandre Oba / Banca: Ariel Antonio Mendes / Resumo: A busca por alimentos seguros faz da irradiação umas das técnicas de tratamentos de alimentos mais promissoras nos dias atuais, porém, a falta de informações por parte dos consumidores tem sido algo a se destacar. O objetivo do trabalho de pesquisa foi avaliar o efeito da irradiação nas características físicoquímicas, sensoriais e microbiológicas da carne de peito (Pectoralis major) de frangos de corte congelada e armazenada. Foram utilizados 96 bandejas plásticas de polietileno expandido, com aproximadamente 650 gramas de filés por bandeja, das quais 48 bandejas foram recobertas por filme plástico (PVC) e a outra metade (48) foram recobertas por sacolas plásticas e submetidas a vácuo. As bandejas foram submetidas ao congelamento, em túnel por cerca de 9 horas a -36°C e mantidas sob congelamento (-20°C). A irradiação foi realizada em um irradiador comercial de grande porte, por meio de raios gama, provenientes do radioisótopo Cobalto-60 utilizado como fonte, a uma taxa de dose de 4 kGy/h. O delineamento experimental utilizado foi o inteiramente casualizado, com 4 repetições, 24 tratamentos de acordo com um esquema fatorial 2 x 3 x 4, dois tipos de embalagens (filme e vácuo), três doses de radiação (0; 1,5 e 3,0 kGy) e quatro períodos de armazenamento (0, 2, 4 e 6 meses). Os resultados mostram que com a irradiação houve aumentou significativo na oxidação do músculo (TBARS), alterações na cor com aumento na luminosidade e intensidade de vermelho e redução no amarelo. O vácuo promoveu redução nos valores de TBARS, força de cisalhamento,...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The search for safety foods makes the irradiation one of the most promising treatments of food, but a lack of information from consumers is something that has to be seen. The aim of this study was to evaluate the radiation effects on physics, chemicals, sensorial and microbiological characteristics of frozen and stored broiler breast meat (Pectoralis major). It was used 96 plastic trays of expanded polyethylene, with approximately 650 grams of filets (breast meat) per tray, 48 trays were covered with plastic film (PVC) and the other half (48 trays) were covered with plastic bags and submitted to vacuum. The trays with the samples were frozen in freezing tunnels for about 9 hours to -36°C and then maintained under freezing temperatures (-20°C). The radiation was accomplished in a commercial reactor, using high-energy gamma radiation, given off by a radioactive source (radioisotope Cobalt-60 - 4 kGy/h).A completely randomized experimental design was used, in a factorial arrangement 2 x 3 x 4 - 2 packing types (plastic film and vacuum), 3 irradiation levels (0; 1,5 e 3,0 kGy) and 4 storage periods (0, 2, 4 e 6 months).The results showed that meat radiation process took to an oxidation increase (TBARS) and to a color alteration, increasing brightness and red values and decreasing the yellow intensity. Vacuum action reduced the TBARS values, shear force, volume and protein of exudates liquid and weight loss during cooking. Radiation reduced the sensorial characteristics, mainly when the radiation level used was 3,0 kGy. However, the use of vacuum was positive, increasing sensorial parameters. The radiation use was effective in the elimination of fecal/totals coliforms, independently of the storage. / Doutor