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The Main Injector Neutrino Oscillation Search (MINOS) is a two detector long-baseline neutrino experiment designed to study the disappearance of muon neutrinos. MINOS will test the v[subscript mu] → v[subscript tau] oscillation hypothesis and measure precisely [Delta]m[superscript 2 subscript 23] and sin² 2[theta subscript 23] oscillation parameters. The source of neutrinos for MINOS experiment is Fermilab's Neutrinos at the Main Injector (NuMI) beamline. The energy spectrum and the composition of the beam is measured at two locations, one close to the source and the other 735 km downstream in the Soudan Mine Underground Laboratory in northern Minnesota. The precision measurement of the oscillation parameters requires an accurate prediction of the neutrino flux at the Far Detector. This thesis discusses the calculation of the neutrino flux at the Far Detector and its uncertainties. A technique that uses the Near Detector data to constrain the uncertainties in the calculation of the flux is described. The data corresponding to an exposure of 2.5×1020 protons on the NuMI target is presented and an energy dependent disappearance pattern predicted by neutrino oscillation hypotheses is observed in the Far Detector data. The fit to MINOS data, for given exposure, yields the best fit values for [Delta]m[superscript 2 subscript 23] and sin² 2[theta subscript 23] to be (2.38[superscript +0.20, subscript -0.16] x 10⁻³eV²/c⁴ and 1.00[subscript -0.08], respectively. / text

published_or_final_version / abstract / Physics / Master / Master of Philosophy

published_or_final_version / Physics / Master / Master of Philosophy

No description available.

The neutrino fluxes from the neutral current (NC), charged current (CC), and elastic scattering (ES) neutrino interactions in the salt phase of SNO have been extracted. The signals were extracted above an energy threshold of 4MeV, which is the lowest energy threshold at which the neutrino signals have been extracted from SNO to date. To achieve this low energy threshold the internal and external radioactive background signals have also been measured. The $^{8}$B neutrino fluxes for the 4MeV threshold were found to be \begin{eqnarray*} \Phi_{CC} & = & 1.60 ~^{+0.04}_{-0.04}~(\mbox{stat}) ~^{+0.06}_{-0.06}~(\mbox{syst}) \times 10^6 \mbox{cm}^{-2} \mbox{sec}^{-1},\\ \Phi_{NC} & = & 4.84 ~^{+0.16}_{-0.16}~(\mbox{stat}) ~^{+0.29}_{-0.32}~(\mbox{syst}) \times 10^6 \mbox{cm}^{-2} \mbox{sec}^{-1},\\ \Phi_{ES} & = & 2.75 ~^{+0.23}_{-0.23}~(\mbox{stat}) ~^{+0.25}_{-0.26}~(\mbox{syst}) \times 10^6 \mbox{cm}^{-2} \mbox{sec}^{-1}. \end{eqnarray*} \noindent These results are in agreement with the values published in ~\cite{SNO3} and the NC flux is in agreement with the standard solar model calculation from ~\cite{bp2004}. The published fluxes were \begin{eqnarray*} \Phi_{CC} &= & 1.68 ~^{+0.06}_{-0.06}~(\mbox{stat}) ~^{+0.08}_{-0.09}~(\mbox{syst}) \times 10^6 \mbox{cm}^{-2} \mbox{sec}^{-1} , \\ \Phi_{NC} &= & 4.94 ~^{+0.21}_{-0.21}~(\mbox{stat}) ~^{+0.38}_{-0.34}~(\mbox{syst}) \times 10^6 \mbox{cm}^{-2} \mbox{sec}^{-1}, \\ \Phi_{ES} &= & 2.35 ~^{+0.22}_{-0.22}~(\mbox{stat}) ~^{+0.15}_{-0.15}~(\mbox{syst}) \times 10^6 \mbox{cm}^{-2} \mbox{sec}^{-1}. \end{eqnarray*} \noindent The uncertainties on the extracted NC and CC fluxes are significantly smaller than on the published values. A comparison of the total uncertainty from flux measurements presented here and those published are given below. \begin{table}[htp] \begin{center} \begin{tabular}{|c|c|c|} \hline & uncertainties presented here (\%) & uncertainties from ~\cite{SNO3} (\%) \\ \hline $\Phi_{CC}$ & $~^{+4.6}_{-4.4}$ & $~^{+5.9}_{-6.4}$ \\ \hline $\Phi_{NC}$ & $~^{+6.8}_{-7.4}$ & $~^{+8.9}_{-8.2}$ \\ \hline $\Phi_{ES}$ & $~^{+12.3}_{-12.6}$ & $~^{+11.3}_{-11.3}$ \\ \hline \end{tabular} \label{funcert1} \end{center} \end{table} The shape of the CC energy spectrum has also been extracted with the 4MeV energy threshold. The uncertainties on the extracted fluxes are smaller than what was previously published. The CC spectrum gives a measure of the neutrino energy shape distortion due to neutrino oscillations. The uncertainties on the lowest energy bins in the extracted CC spectrum are much larger than the predicted distortion. We are therefore not sensitive to the upturn in the neutrino survival probability at lower energies predicted by neutrino oscillations in the large mixing angle (LMA) region. / Thesis (Ph.D, Physics, Engineering Physics and Astronomy) -- Queen's University, 2007-12-19 13:58:16.601

The SNO+ experiment is a multi-purpose neutrino detector which is under construction in the SNOLAB facility in Sudbury, Ontario. SNO+ will search for neutrinoless double beta decay, and will measure low energy solar neutrinos. This thesis will describe three main development activities for the SNO+ experiment: the measurement of the timing parameters for the liquid scintillator cocktail, using those timing parameters to estimate the ability of SNO+ to discriminate alpha and beta events in the detector, and a sensitivity study that examines how solar neutrino data can constrain a light sterile neutrino model. Characterizing the timing parameters of the emission light due to charged-particle excitation in the scintillator is necessary for proper reconstruction of events in the detector. Using data obtained from a bench-top setup, the timing profile was modelled as three exponential components with distinct timing coefficients. Also investigated was the feasibility of using the timing profiles as a means to separate alpha and beta excitation events in the scintillator. The bench-top study suggested that using the peak-to-total method of analyzing the timing profiles could remove >$99.9% of alpha events while retaining >$99.9% of beta events. The timing parameters measured in the test set-up were then implemented in a Monte Carlo code which simulated the SNO+ detector conditions. The simulation results suggested that detector effects reduce the effectiveness of discriminating between alpha and beta events using the peak-to-total method. Using a more optimal method of analyzing the timing profile differences, specifically using a Gatti filter, improved the discrimination capability back to the levels determined in the bench-top setup. One of the physics goals of SNO+ is the first precision measurement of the pep solar neutrino flux at the level of about 5% uncertainty. A study was performed to investigate how current solar neutrino data constrains the allowed parameters of a light 3+1 sterile neutrino model. The impact of adding a SNO+ pep solar neutrino measurement on the allowed parameters of the sterile model was then examined. / Thesis (Ph.D, Physics, Engineering Physics and Astronomy) -- Queen's University, 2014-04-28 20:52:42.41

Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 38-40). / vi, 40 leaves, bound ill. 29 cm

Thesis (Ph. D.)--University of Sydney, 2001. / Squiggly right arrow used in title. Title from title screen (viewed Apr. 23, 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Physics, Faculty of Science. Degree awarded 2001; thesis submitted 2000. Includes bibliography. Also available in print form.

Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.