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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.
11

Simulation of cascades for the IceCube neutrino telescope : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science, University of Canterbury /

Hickford, Stephanie. January 2007 (has links)
Thesis (M. Sc.)--University of Canterbury, 2007. / Typescript (photocopy). Includes bibliographical references (p. 62-63). Also available via the World Wide Web.
12

Cascade reconstruction analysis with the IceCube neutrino detector : M.Sc thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Physics, University of Canterbury /

McCartin, Joseph. January 1900 (has links)
Thesis (M. Sc.)--University of Canterbury, 2009. / Typescript (photocopy). "July 15, 2009." Includes bibliographical references (p. 71-73). Also available via the World Wide Web.
13

A search for periodic neutrino signals and gamma-ray burst neutrinos with the Sudbury Neutrino Observatory

Tsang, Ka-vang. January 2005 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2005. / Title proper from title frame. Also available in printed format.
14

Tests of neutrino interaction models with the MicroBooNE detector

Rafique, Aleena January 1900 (has links)
Doctor of Philosophy / Department of Physics / Timothy A. Bolton / I measure a large set of observables in inclusive charged current muon neutrino scattering on argon with the MicroBooNE liquid argon time projection chamber operating at Fermilab. I evaluate three neutrino interaction models based on the widely used GENIE event generator using these observables. The measurement uses a data set consisting of neutrino interactions with a final state muon candidate fully contained within the MicroBooNE detector. These data were collected in 2016 with the Fermilab Booster Neutrino Beam, which has an average neutrino energy of 800 MeV, using an exposure corresponding to 5e19 protons-on-target. The analysis employs fully automatic event selection and charged particle track reconstruction and uses a data-driven technique to separate neutrino interactions from cosmic ray background events. I find that GENIE models consistently describe the shapes of a large number of kinematic distributions for fixed observed multiplicity, but I show an indication that the observed multiplicity fractions deviate from GENIE expectations.
15

Many-body Problems in the Theory of Stellar Collapse and Neutron Stars / Mångkropparsproblem inom teorin för neutronstjärnor och supernovaexplosioner

Olsson, Emma January 2004 (has links)
<p>When modelling the collapse of massive stars leading to supernova explosions and the cooling of neutron stars, understanding the microphysical processes, such as the interaction of neutrinos within a dense medium are of vital importance. The interaction of neutrinos with nucleons (neutrons and protons) is altered by the presence of the medium, compared to the same process with free nucleons. Neutrino scattering and production processes may be characterized in terms of the excitations that are created or destroyed in the nuclear medium. One way to analyse the effects of the medium is by using Landau's theory of normal Fermi liquids. This theory gives simple relationships between physical quantities such as the spin susceptibility or the response to a weak interaction probe in terms of Landau parameters, that are measures of the interaction between quasiparticles. One problem when using Landau Fermi liquid theory for nucleon matter is that the interaction has a tensor component. The tensor interaction does not conserve the total spin and, as a consequence, there are generally contributions to long-wavelength response functions from states that have more than one quasiparticle-quasihole pair in the intermediate state. Such contributions cannot be calculated in terms of Landau parameters alone, since in the usual formulation of Landau theory, only singlepair excitations are considered. In this thesis three problems are addressed. First, we obtain bounds on the contributions from more than one quasiparticle-quasihole pair by using sum-rule arguments. Second, we derive expressions for static response functions allowing for the tensor components of the interaction. We analyse which the most important effects are on the static response of nucleon matter, and find that the major contributions comes from renormalization of coupling constants and transitions to states with more than one quasiparticle-quasihole pair. Third, we show how contributions to the dynamical response coming from states containing two quasiparticle-quasihole pairs may be evaluated in terms of Landau theory if one allows for the effect of collisions in the Landau kinetic equation. We consider the case of asymmetric nuclear matter, and our work goes beyond earlier works in that they contain the effects of collisions in addition to those of the mean field.</p>
16

Many-body Problems in the Theory of Stellar Collapse and Neutron Stars / Mångkropparsproblem inom teorin för neutronstjärnor och supernovaexplosioner

Olsson, Emma January 2004 (has links)
When modelling the collapse of massive stars leading to supernova explosions and the cooling of neutron stars, understanding the microphysical processes, such as the interaction of neutrinos within a dense medium are of vital importance. The interaction of neutrinos with nucleons (neutrons and protons) is altered by the presence of the medium, compared to the same process with free nucleons. Neutrino scattering and production processes may be characterized in terms of the excitations that are created or destroyed in the nuclear medium. One way to analyse the effects of the medium is by using Landau's theory of normal Fermi liquids. This theory gives simple relationships between physical quantities such as the spin susceptibility or the response to a weak interaction probe in terms of Landau parameters, that are measures of the interaction between quasiparticles. One problem when using Landau Fermi liquid theory for nucleon matter is that the interaction has a tensor component. The tensor interaction does not conserve the total spin and, as a consequence, there are generally contributions to long-wavelength response functions from states that have more than one quasiparticle-quasihole pair in the intermediate state. Such contributions cannot be calculated in terms of Landau parameters alone, since in the usual formulation of Landau theory, only singlepair excitations are considered. In this thesis three problems are addressed. First, we obtain bounds on the contributions from more than one quasiparticle-quasihole pair by using sum-rule arguments. Second, we derive expressions for static response functions allowing for the tensor components of the interaction. We analyse which the most important effects are on the static response of nucleon matter, and find that the major contributions comes from renormalization of coupling constants and transitions to states with more than one quasiparticle-quasihole pair. Third, we show how contributions to the dynamical response coming from states containing two quasiparticle-quasihole pairs may be evaluated in terms of Landau theory if one allows for the effect of collisions in the Landau kinetic equation. We consider the case of asymmetric nuclear matter, and our work goes beyond earlier works in that they contain the effects of collisions in addition to those of the mean field.
17

Recherche d'un flux diffus de neutrinos tauiques d'origine cosmique dans le détecteur IceCube

Bechet, Sabrina 22 October 2012 (has links)
Le détecteur IceCube est constitué d'un réseau de modules optiques digitaux (DOMs) déployés sur un volume d'1 km³ dans la glace antarctique. Les DOMs enregistrent la lumière Cerenkov émise par les particules secondaires issues des interactions des neutrinos avec la glace. Selon la répartition géographique des signaux lumineux dans la glace, on peut différencier les différentes saveurs de leptons et ainsi identifier la saveur du neutrino primaire. Les modèles astrophysiques prédisent une production dominante de neutrinos électroniques et muoniques au sein d'accélérateurs cosmiques. Cependant, lors de leur propagation dans l'univers, ces neutrinos oscillent et on s'attend à observer sur Terre le même flux des trois saveurs de neutrinos. Comme la production de neutrinos tauiques dans l'atmosphère est négligeable, ce canal est affecté d'un bruit de fond intrinsèque quasi nul.<p><p>Ce travail porte sur la détection de neutrinos tauiques d'origine cosmique. A haute énergie (E>PeV), le lepton tau, produit par le neutrino tauique, se propage sur une centaine de mètres avant de se désintégrer. Nous optimisons notre recherche pour le canal de désintégration muonique qui, s'il se produit dans le volume de détection, présente une signature unique. En effet, les différences de masse du tau et du muon induisent des différences quant à leur processus de perte d'énergie qui mènent à une différence de luminosité le long des traces du tau et du muon. <p><p>Nous avons développé une observable originale reposant sur les charges enregistrées par les différents DOMs pour caractériser la luminosité le long d'une trace afin de différencier les traces de muons de celles de taus se désintégrant en muon .Cependant, au niveau de déclenchement du détecteur, on est confronté à un bruit de fond de muons atmosphèriques un million de fois supérieur au signal. Nous avons donc mis en place une série de coupures afin de réduire ce bruit de fond et ainsi augmenter la pureté de notre échantillon. <p><p>Enfin l'application de ces coupures sur un échantillon de données réelles enregistrées durant la saison 2009-2010 et l'absence de signal détecté permettent de poser une limite supérieure sur le flux de neutrinos tauiques. Ceci constitue la première limite expérimentale pour des neutrinos tauiques d'énergies inférieures à 20 PeV. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
18

Theoretical and Phenomenological Studies of Neutrino Physics

Blennow, Mattias January 2007 (has links)
This thesis is devoted to the theory and phenomenology of neutrino physics. While the standard model of particle physics has been extremely successful, it fails to account for massive neutrinos, which are necessary to describe the observations of neutrino oscillations made by several different experiments. Thus, neutrino physics is a possible window for exploring the physics beyond the standard model, making it both interesting and important for our fundamental understanding of Nature. Throughout this thesis, we will discuss different aspects of neutrino physics, ranging from taking all three types of neutrinos into account in neutrino oscillation experiments to exploring the possibilities of neutrino mass models to produce a viable source of the baryon asymmetry of the Universe. The emphasis of the thesis is on neutrino oscillations which, given their implication of neutrino masses, is a phenomenon where other results that are not describable in the standard model could be found, such as new interactions between neutrinos and fermions. / QC 20100630

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