Thesis (M.S.)--University of Delaware, 2005. / Principal faculty advisors: Martin Swany, Dept.. of Computer & Information Sciences; and David Seckel, Dept. of Physics & Astronomy. Includes bibliographical references.

Thesis (M. Sc.)--Carleton University, 1989. / Also available in electronic format on the Internet.

Thesis (M. Sc.)--Carleton University, 1990. / Also available in electronic format on the Internet.

Universiẗat, Diss., 2001--Tübingen. / Erscheinungsjahr an der Haupttitelstelle: 2000.

Orientador: Orlando Luis Goulart Peres / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-19T13:26:00Z (GMT). No. of bitstreams: 1 TapiaHerrera_LuisCarlos1982-_M.pdf: 3198399 bytes, checksum: bd22a4c22f21d4db7bc8f29cda4bd521 (MD5) Previous issue date: 2011 / Resumo: Apresentamos neste trabalho um estudo da fenomenologias dos neutrinos, que inicia com um modelo além do Modelo Padrão, que gera massa e decaimento para os neutrinos. O modelo foi proposto por Gelmini e Roncadelli [3], no modelo é introducido um tripleto escalar que interage com o dubleto de Higgs a través de um potencial escalar. O tripleto interage também com os leptons da teoria a través de um potencial de Yukawa, é este potencial que conjuntamente com a quebra espontânea da simetria gera as massas e decaimentos para os neutrinos. O modelo foi descartado experimentalmente mas modelos mais gerais que estão baseados no modelo de Gelmini e Roncadelli, ainda podem ser testados experimentalmente. Como seguinte passo no nosso trabalho, estudamos os fluxos de neutrinos de Supernovas que aconteceram no passado do Universo e que chegam até à Terra. Estudamos os efeitos de oscilação na matéria, por causa de que o neutrino atravessa médios de densidades altas dentro da Supernova. Fizemos a comparação dos fluxos de neutrinos e antineutrinos eletrônicos, levando em conta dois casos com e sem oscilação. Encontramos que a oscilação faz com que o fluxo de neutrinos e antineutrinos seja menor, e mais quente para energias maiores a 10 MeV. Estudamos conjuntamente o decaimento e suas consequencias no fluxo de neutrinos de Supernova relíquia. Encontramos uma forte dependência com a hierarquia de massas dos neutrinos. Concluímos que se a hierarquia de massas é normal, o decaimento faz com que o fluxo de neutrinos e antineutrinos eletrônicos seja incrementado. Se a hierarquia é invertida encontramos que o fluxo dos dois tipos de neutrinos é suprimido. Fizemos também uma comparação dos fluxos obtidos neste trabalho, com valores de fluxos reportados na literatura. Finalmente estudamos o comportamento do número de eventos dos fluxos de neutrinos e antineutrinos eletrônicos, para distintos tempos de vida dos neutrinos / Abstract: Here we present a study of the phenomenology of neutrinos, which starts with a model beyond the Standard Model, which generates mass and decay to neutrinos. The model was proposed by Gelmini and Roncadelli cite Gelmini: 1981, the model needs a triplet that interacts with the scaling doublet Higgs through different potential climb. The triplet also interacts with leptons theory through different potential of Yukawa, is this potential which, together with spontaneous symmetry breaking generates the masses and decays to neutrinos. The model was experimentally ruled out but more general models that are based on the model of Gelmini and Roncadelli, can still be tested experimentally. As a next step in our work, we study the flow of neutrinos from supernovae that happened in the past of the universe and reach the Earth. We studied the effects of oscillations in matter, because of the neutrino cross mean high densities within the Supernova. We compared the flow of neutrinos and antineutrinos electronics, taking into consider two cases with and without oscillation. We have found that the oscillation causes the flux of neutrinos and antineutrinos is smaller and warmer to higher energies to 10 MeV We studied together and the decay and its consequences in the flow of neutrinos from supernova relic. We find a strong dependence on the hierarchy mass of neutrinos. We conclude that if the hierarchy is normal masses, the decay is that the flux of neutrinos and electronic antineutrinos is incremented. If the hierarchy is found that the reverse flow of the two types of neutrinos is deleted. We also a comparison of fluxes obtained in this work, with values of flows reported in the literature. Finally we study the behavior of the number of events flows of neutrinos and antineutrinos electronics, for different lifetimes of neutrinos / Mestrado / Física / Mestre em Física

Orientador: Marcelo Moraes Guzzo / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-20T17:05:52Z (GMT). No. of bitstreams: 1 Oliveira_RobertoLeandroNevesde_D.pdf: 2779754 bytes, checksum: a4305b15e2ab247f07cb3cf74146335f (MD5) Previous issue date: 2012 / Resumo: Nesta tese, estudamos algumas consequências fenomenológicas da introdução do fenômeno de dissipação quântica na fenomenologia de oscilações de neutrinos em duas famílias. Utilizando a abordagem de equação mestra to tipo Lindblad-Kossakowski e o critério de completa positividade, descrevemos diferentes modelos para o sistema de oscilação de neutrinos sujeitos aos efeitos dissipativos causados por considerarmos que estes estão abertos a interagirem com o meio a seu redor. Investigamos como incluir os efeitos dissipativos para oscilação de neutrinos no vacuo e para quando os efeitos causados pelo potencial efetivo de matéria também estão incluídos no modelo de oscilação. Por m, aplicamos a fenomenologia estudada ao experimento MINOS como forma de observar como os efeitos dissipativos se comportam frente aos dados experimentais / Abstract: In this thesis, we study the introduction of the quantum dissipation phenomenon and the phenomenological consequences in the model of neutrino oscillations in two families. Using the Lindblad-Kossakowski master-equation approach and the complete positivity condition, we describe different models for the neutrino oscillation system subject to dissipative effects, that are caused when we consider that neutrinos can interact with the environment around them, forming a open quantum system. We investigate as to include the dissipative e ects in neutrino oscillation in vacuum and when the effects of the efective potential of matter are also included in the model of oscillation. Finally, we apply the phenomenology studied to MINOS experiment as a way to observe the behavior of the dissipative e effects from experimental data / Doutorado / Física / Doutor em Ciências

The IceCube Neutrino Observatory consists of a lattice of 5160 photomultiplier tubes (PMTs)<p>which monitor one cubic kilometer of deep Antarctic ice at the geographic South Pole.<p>IceCube was primarily designed to detect neutrinos of energies greater than O(100 GeV).<p>Due to subfreezing ice temperatures, the photomultipliers' dark noise rates are particularly<p>low which enables IceCube to search for neutrinos from galactic supernovae by detecting<p>bursts of MeV neutrinos emitted during the core collapse and for several seconds following.<p>For that purpose, a dedicated online supernova DAQ system records the total number of hits<p>in the detector, without any further information from the PMTs, and generates supernova<p>candidate triggers in case of a significant detector rate enhancement. A new feature to the<p>standard DAQ, called HitSpooling, was implemented in IceCube during this thesis. The<p>HitSpooling system is implemented in the standard DAQ system and buffers the complete<p>raw data stream of the photomultipliers for several hours or days. By reading out time periods<p>of HitSpool data around supernova candidate triggers, generated by the online supernova<p>DAQ system, we overcome the limitations of the latter and have access to the entire information<p>of the detector in case of a supernova. Furthermore, HitSpool data is a powerful<p>source for studying and understanding the noise behavior of the detector as well as background<p>processes coming from atmospheric muons. The idea of HitSpooling was developed in the<p>scope of this thesis and is the basis of the work at hand. The developed interface between the<p>standard DAQ and the supernova DAQ system is presented. The correlated dark noise component<p>in optical modules of IceCube is quantified for the first time and possible explanations<p>are discussed. The possibility of identifying triggering and subthreshold atmospheric muons<p>in HitSpool data and subtracting them from a possible supernova signal is analyzed. Furthermore,<p>the conversion from HitSpool data to supernova DAQ type data was developed<p>which allows for a comparison of both data types with respect to lightcurves and significances<p>of selected supernova candidate triggers. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

Orientador: Pedro Cunha de Holanda / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-22T08:38:27Z (GMT). No. of bitstreams: 1 Boriero_DanielFrancisco_D.pdf: 1994859 bytes, checksum: a59e512b9fdcb71d04bb5f9702f0fb60 (MD5) Previous issue date: 2013 / Resumo: Cosmologia de neutrinos é a atividade de pesquisa dedicada ao teste de propriedades de neutrinos através de observáveis cosmológicos. Particularmente, as propriedades estudadas e testadas ao longo desta tese de doutorado foram à massa dos neutrinos e o número de estados estéreis. Ambas as propriedades são motivadas pela observação em experimentos terrestres do fenômeno de oscilação entre estados de interação. Diferentemente da existência de estados massivos, os indícios da existência de estados estéreis são tenuemente sugeridos, contudo ambas as propriedades representariam um grande impacto no modelo cosmológico caso sejam observados sinais positivos de suas existências e por esse motivo justificam-se suas análises. A utilização da cosmologia como um laboratório de física de neutrinos é possível graças à imensa abundância de neutrinos remanescentes do universo primordial além da sensibilidade sem precedentes das observações realizadas. Telescópios e detectores em planejamento ou em implementação supostamente alcançarão a sensibilidade equivalente aos valores mínimos das massas determinados pelo fenômeno de oscilação. A perspectiva de tais sensibilidades experimentais deve ser acompanhada pelo aumento equivalente da precisão obtida nas previsões teóricas dos efeitos pelos quais pretende-se detectar a presença de neutrinos massivos ou de estados estéreis. Nesta tese de doutorado, além de ser detalhadamente desenvolvida a teoria e a metodologia convencionais na análise de dados cosmológicos para obtenção de medidas ou limites para estes dois parâmetros, também foram desenvolvidos métodos para aumentar a precisão da previsibilidade teórica. Foram abordados dois desafios teóricos prementes, a imprecisão das previsões no regime não-linear de perturbação para neutrinos massivos e a degenerescência em relação aos parâmetros de modelos cosmológicos estendidos. As melhorias obtidas não compõem soluções definitivas, mas sim metodologias a serem desenvolvidas sistematicamente ao longo da obtenção de novos dados reais e simulados. / Abstract: Neutrino cosmology is the research activity dedicated to test neutrino properties by cosmological observables. Specially, the properties studied and tested along this graduate research were the neutrino mass and the sterile states. Both properties are motivated from observations in terrestrial experiments of the phenomenon of oscillation between interaction states. Differently from the existence of massive states, the signals of sterile states are weakly suggested, however both properties would mean a sizeable impact in the cosmological model in case any positive signal is detected and, therefore, their analysis are justified. The utilization of cosmology as a laboratory of neutrino physics is possible thanks to the high abundance of remaining neutrinos from the primordial universe, besides the unprecedented sensitivity of experimental observations. Telescopes and detectors planned or under construction will supposedly reach the sensitivity equivalent to the minimal neutrinos masses given by the oscillation phenomenum. The perspective of such experimental sensitivities must be followed by the equivalent improvement in the theoretical predictability for the effects with which it is intended to detect a positive signal of massive neutrinos or sterile states. In this Ph.D. Thesis, besides being developed in detail the theory and methodology used in the analysis of cosmological data to measure or constrain these two parameters, we also developed methods and tools to improve the theoretical predictability. Two pressing theoretical challenges were addressed, the imprecision of the predictions in the non-linear regime of perturbations for massive neutrinos and the degeneracy related to parameters of extended cosmological models. The improvements obtained do not make up a definitive solution, but rather methodologies to be systematically developed along with the achivement or the eventuality of new real and simulated data. / Doutorado / Física / Doutor em Ciências

京都大学 / 新制・課程博士 / 博士(理学) / 甲第23004号 / 理博第4681号 / 新制||理||1671(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)准教授 WENDELL Roger, 教授 中家 剛, 准教授 久徳 浩太郎 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

Dark Matter (DM) is believed to consist ofWeakly Interactive Massive Particles (WIMPs) which interact only through gravity and the weak nuclear force. These particles can become trapped in gravitational wells such as the Sun and a theoretical value of the capture rate can be calculated. At high particle density the WIMPs annihilating spontaneously into Standard Model (SM) particles. Due to particle equilibrium the total annihilation rate can be related to the capture rate by a simple expression. This report will focus on calculating the capture rate and the related annihilation rate as well as calculating the neutrino 　ux of the Sun. At rst we will give a brief introduction to cosmology and a theoretical argument for the WIMPs as the prime DM candidate. Then we will look at the theoretical background and the mechanism through which WIMPs become trapped and evaporate or annihilate. Finally we will perform a numerical analysis of the WIMP cycle within the Sun and calculate the capture rate for a variety of theoretical WIMP masses. We will look at the capture rate due to scattering both by hydrogen nucleii and by more massive elements. The Scattering by hydrogen will be the prime contributor to the total capture rate and is the only spin dependent contribution.