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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

High energy neutrino-nucleon interactions with an electron in the final state

Gee, Manyee Ngai. January 1984 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1984. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 209-213).
132

Cross section measurements in the Main Injector Particle Production (FNAL-E907) experiment at 58 GeV Energy

Günaydın, Yusuf Oğuzhan. Onel, Y. January 2009 (has links)
Thesis supervisor: Yasar Onel. Includes bibliographic references (p. 97-98).
133

Models for carbon-oxygen stars of one solar mass in the late stages of evolution

Bautz, Laura Patricia, January 1967 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1967. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
134

Accelerator systems and instrumentation for the NuMI neutrino beam

Zwaska, Robert Miles, January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2005. / Vita. Includes bibliographical references.
135

A search for matter enhanced neutrino oscillations through measurements of day and night solar neutrino fluxes at the Sudbury Neutrino Observatory /

Miknaitis, Kathryn Kelly Schaffer. January 2005 (has links)
Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (p. 209-222).
136

A measurement of muon neutrino disappearance with the MINOS detectors and NuMI beam

Ospanov, Rustem. January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.
137

Massive Neutrinos: Phenomenological and Cosmological Consequences / Neutrinos Massivos: Consequências fenomenológicas e cosmológicas

Yuber Ferney Perez Gonzalez 01 December 2017 (has links)
The XX century witnessed the quantum and relativistic revolutions in physics. The development of these two theories, namely, Quantum Mechanics and Relativity, was the inception of many crucial discoveries and technological advances. Among them, one stands out due to its uniqueness, the neutrino discovery. However, several neutrino properties are still obscure. Neutrinos are the only fundamental particles whose nature is currently unknown. Such fermions can either be different from their antiparticles, i.e., Dirac fermions, or be their own antiparticles, that is, Majorana fermions. On the other hand, the smallness of neutrino masses is a problem seemingly related to the neutrino nature; thus, as essential task consists in addressing the phenomenologically viable models in both cases. Furthermore, it is important to search for other physical process in which the neutrino nature may manifest through different experimental signatures. A rather difficult but promising method corresponds to the detection of the cosmic neutrino background, viz. neutrinos which are relics from the Big Bang. Previous works have shown that detection rates for Dirac and Majorana neutrinos can give different results. Nevertheless, this distinction was obtained considering the Standard Model framework only. Therefore, it is important to understand the consequences of having Non-Standard Interactions contributing to the detection of neutrinos from the cosmic background. Another remarkable relic predicted by Cosmology is the unidentified Dark Matter, composing ~25% of the Universe. All searches regarding the Weakly Interacting Massive Particle, one of the principal candidates for Dark Matter, have given negative results; this has compelled experiments to increase their sensitivity. Notwithstanding, neutrinos may stand in the way of such experimental searches given that they may constitute an irreducible background. In this thesis, we will address these three different phenomena, neutrino mass models, detection of the cosmic neutrino background and the neutrino background in Dark Matter searches, by considering the different characteristics in each case. In the study of neutrino mass models, we will consider models for both Majorana and Dirac neutrinos; specifically, we will probe the neutrinophilic two-Higgs-doublet model. Regarding the detection of relic neutrinos, we will analyse the consequences of the existence of the beyond Standard Model physics in the capture rate by tritium. Finally, we will scrutinize the impact of neutrinos in Direct Detection WIMP searches, by considering Standard Model plus additional interactions in the form of simplified models. / Ao longo do século XX testemunhamos as revoluções quântica e relativista que aconteceram na Física. O desenvolvimento da Mecânica quântica e da teoria da relatividade foi o prelúdio de inúmeras descobertas e avanços tecnológicos fundamentais; em particular, a descoberta dos neutrinos. No entanto, a sua total compreensão ainda é um mistério para a física de partículas. Entendidos como partículas fermiônicas fundamentais, os neutrinos possuem sua natureza desconhecida. Podendo ser diferentes de suas antipartículas, denominadas férmions de Dirac, ou também podendo ser as suas próprias antipartícula, sendo conhecidas como férmions de Majorana. Por outro lado, o valor de sua massa continua sendo um problema em aberto, supostamente relacionado à sua natureza. Portanto, é importante estudarmos modelos fenomenológicos viáveis para as duas naturezas possíves dos neutrinos. Além disso, é necessário procurar outros processos físicos cujos resultados experimentais sejam distintos de acordo com a natureza do neutrino. Um método bastante difícil, mas promissor, corresponde à detecção do fundo de neutrinos cósmicos, isto é, os neutrinos relíquia do Big Bang. Análises prévias mostraram que as taxas de detecção para neutrinos de Dirac e de Majorana resultam em valores distintos. Porém, este resultado foi obtido supondo como base o Modelo Padrão; assim, é crucial entender as possíveis consequências da existência de interações desconhecidas na detecção dos neutrinos da radiação cósmica de fundo. Outra relíquia notável prevista pela Cosmologia é a desconhecida Matéria Escura, que compõe ~25% do Universo. Todas as buscas por WIMPs (do inglês Weakly Interactive Massive Particles), um dos principais candidatos a Matéria Escura, tem dado resultados negativos. Isto tem forçado a criação de experimentos cada vez mais sensíveis. Contudo, os neutrinos poderão ser um obstáculo nessas buscas experimentais, pois estes convertir-se-ão em um fundo irredutível. Na presente tese, abordaremos estes três fenômenos diferentes, modelos de massa para os neutrinos, a detecção do fundo de neutrinos cósmicos e o fundo de neutrinos em experimentos de detecção direta de Matéria Escura, considerando as distintas características em cada caso. No estudo dos modelos de massa para os neutrinos consideraremos modelos para neutrinos de Majorana e Dirac; exploraremos modelos neutrinofílicos com dois dubletos de Higgs. Enquanto à detecção dos neutrinos relíquia, analisaremos as consequências da presença de física além do Modelo Padrão na taxa de captura pelo trítio. Finalmente, examinaremos o impacto dos neutrinos em experimentos de detecção direta de WIMPs, supondo as interações do Modelo Padrão junto com interações adicionais na forma de modelos simplificados.
138

Neutrino charm production and a limit to neutrino oscillations

Bailey, David Charles. January 1983 (has links)
No description available.
139

The Implications of Gauging Lepton Flavour Symmetries for Dark Matter and Neutrino Masses

Plestid, Ryan 11 1900 (has links)
The Standard Model of particle physics is a phenomenologically successful description of the strong, weak, and electromagnetic interactions at all currently accessible energy scales with few exceptions \cite{Agashe:2014kda}. The notable deficiencies of the Standard Model are its inability to explain the matter anti-matter asymmetry, the existence of neutrino oscillations \cite{Fukuda:1998mi,Ahmad:2002jz}, the anomalous magnetic moment of the muon \cite{Bennett:2006fi,Hagiwara:2011af}, and its failure to provide a suitable candidate for the gravitationally observed dark matter \citep{Dolgov:1995np}. We explore an extension of the Standard Model that introduces a new gauge symmetry $L_\mu-L_\tau$ along with three right-handed neutrinos, and a symmetry breaking scalar field. The inclusion of right-handed neutrinos are motivated by the aforementioned neutrino oscillation data while the scalar field is motivated by cosmological bounds on a new $Z'$. We attempt to fit our model to the observed neutrino mass textures in the see-saw limit. Despite having a Lagrangian density with three Yukawa couplings, and four right-handed mass parameters we found the left handed neutrino mass matrix was controlled by only four independent quantities. We were attempting to fit to a set of five measured parameters $\{ \Delta m_{12}^2,\Delta m_{13}^2,\theta_{12},\theta_{23},\theta_{13} \}$. This was found to be impossible with our proposed model. Higher dimensional operators were introduced to allow the model to generate neutrino textures that agree with experiment. Our first minimal model was able to reproduce the correct neutrino textures with the exception of one of either $\theta_{13}$ or $\theta_{12}$ the disagreements was at the level of $25\%$. We found that our model was able to fit to the central value of neutrino data after the introduction of various combinations of dimension-five operators. The parametric dependence of these solutions were found to be incompatible with the $Z'$ as a progenitor of dark matter scenario proposed by Shuve and Yavin \cite{Shuve:2014doa}. The $Z'$ progenitor scenario and the see-saw mechanism seem to be distinct entities in the sense that for the former to be viable the dark matter candidate cannot play a significant role in the generation of neutrino textures. / Thesis / Master of Science (MSc)
140

[en] STUDY OF THE EFFECTS OF STERILE NEUTRINOS IN BETA DECAY EXPERIMENTS / [pt] ESTUDO DOS EFEITOS DE NEUTRINOS ESTÉREIS EM EXPERIMENTOS DE DECAIMENTO BETA

FABIO ALEX PEREIRA DOS SANTOS 22 October 2008 (has links)
[pt] Nesta dissertação, estudamos do ponto de vista fenomenológico, os efeitos de neutrinos estéreis para os observáveis de massas de neutrinos baseado nos dados do experimento LSND e nos resultados divulgados recentemente pela colaboração MiniBooNE. Consideramos observáveis de massa as seguintes quantidades: o parâmetro de massa cinemática cuja medida é realizada em experimentos com o decaimento beta do tritium tendo seu valor atual fornecido pelos experimentos Mainz e Troitsk; a massa efetiva de Majorana, que é uma quantidade que pode ser obtida em experimentos com o duplo decaimento beta sem neutrinos; finalmente, a soma de massas dos neutrinos, a qual é vinculada por dados cosmológicos. Nossa análise é realizada considerando os possíveis ordenamentos de massas para o caso em que temos dois neutrinos estéreis além dos três neutrinos ativos usuais, cuja adição é necessária para explicar os resultados de LSND e MiniBooNE ao mesmo tempo. Neste cenário, temos oito possíveis ordenamentos de massas, os quais dividimos em três grupos. No primeiro grupo, temos que os dois neutrinos estéreis são mais pesados que os três neutrinos ativos. No segundo grupo, os dois neutrinos estéreis são mais leves que os três neutrinos ativos. Cada um destes dois grupos tem possibilidades que dependem do ordenamento de massas dos neutrinos ativos que pode ser normal ou invertido. No terceiro e último grupo temos que um neutrino estéril é mais leve e o outro mais pesado que os três neutrinos ativos. Neste grupo, existem quatro possibilidades de ordenamento associada ao posicionamento dos neutrinos estéreis e ao ordenamento dos neutrinos do setor ativo. Investigamos os observáveis de massas em cada um destes cenários. / [en] In this dissertation we study, from the phenomenological point of view, the effects of sterile neutrinos for the observables related to neutrino masses based on the data of the LSND experiment and on the results releasedrecently by the MiniBooNE collaboration. We consider the following mass related obsevables: the kinematic mass parameter which is obtained in tritium beta decay experiments whose current value is provided by Mainzand Troitsk experiments; the Majorana effective mass, it is a quantity that can be obtained in neutrinoless double beta decay experiments. In additionto these quantities, we also consider the sum of neutrinos masses, which isconstrained by cosmological data. Our analysis is performed by considering the possible mass orderings for the cases where we have two sterile neutrinosbeyond the three standard active neutrinos, whose addition is necessary to explain the results of LSND andMiniBooNE simultaneously. In this scenariot here are eight possible mass orderings, which are divided into three groups.In the first group we have two sterile neutrinos which are heavier thanthe three active neutrinos. In the second group the two sterile neutrinosare lighter than the three active neutrinos. Each of these two groups canbe further divided into 2 subgroups depending on the mass ordering ofthe active neutrinos that can be normal or inverted. In the third and lastgroup we have one sterile neutrino lighter and the other heavier than thethree active neutrinos. In this group there are four possibilities of ordering depending on the positioning of the sterile neutrinos with respect to theactive ones and on the mass ordering of the active states. We investigate systematically the masses observable in each of these scenarios.

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