Initial results are presented for two analyses using data from the recently completed laser calibration system of the time projection chambers for the Tokai-to- Kamioka long baseline neutrino oscillation experiment. Data taken with the first two production time projection chambers, while tested at TRIUMF, has been used to investigate the signal arrival time and subsequently the ionization drift speed and the relative gain of the micromegas and electronics systems. It has been found that an analytic Gaussian t produces the best overall results for establishing an arrival time, having both the lowest standard deviation, of 11 ns, and good amplitude dependence while remaining fast. Using the analytic fit technique the drift speeds of ionization has been found to be in agreement with the expected values at the 2% level. The largest of the contributing errors were found to be due to systematics involved in the calculation of the ionization production time and will be reduced in future. Relative gain analysis results have shown that the gain can be calculated based on a simple model relating the mean signal size of data channels to the variance. Further gain results have shown that an offset found in the laser data can be corrected for by sampling signal amplitudes from channels that do not detect ionization or can remain uncorrected if the fitting for the relative gain includes a correction parameter. Preliminary results of the gain's dependence on the gas temperature and pressure have shown a positive nonzero slope. However, systematic errors were found be large relative to the temperature and pressure ranges. This dependence and its use as a correction for such changes will need to be investigated further at the experiment site in Japan.

Thesis (Ph.D.)--University of Melbourne, School of Physics, 2001. / Typescript (photocopy). Includes bibliographical references (leaves 124-135).

Thesis (M.A.) - Carleton University, 2003. / Includes bibliographical references (p. 219-224). Also available in electronic format on the Internet.

Thesis (M.Sc.) - Carleton University, 2005. / Includes bibliographical references (p. 138-141). Also available in electronic format on the Internet.

Thesis (M.Sc.) - Carleton University, 2005. / Includes bibliographical references (p. 66). Also available in electronic format on the Internet.

Thesis (M.Sc.) - Carleton University, 2005. / Includes bibliographical references (p. 125-130). Also available in electronic format on the Internet.

Thesis (M. Sc.)--Carleton University, 1996. / Also available in electronic format on the Internet.

The Daya Bay experiment is designed to precisely measure short-baseline disappearance of reactor antineutrinos from reactor cores at the Daya Bay nuclear power plant complex in the Guangdong Province of China. It pre- sented the most precise measurements of oscillation parameters sin2 2θ13 = 0.084 ± 0.005 and |∆m2 ee| = (2.42 ± 0.11) × 10−3 eV2 . Background to the antineutrino signals is mainly created by cosmic muons and is effectively suppressed by use of water Cherenkov and RPC muon detectors. This thesis describe testing of RPC detectors prior to their installation at the experi- mental site. Part of the cosmic muons stop in the experiment's antineutrino detectors, and they decay or are captured by 12 C producing 12 B. Isotope 12 B contribute to accidental background. Rates of muon decays in the detectors are estimated in the thesis. The experiment can register electron antineutri- nos from supernova with expected signals around 20 MeV. Energy scale of the detectors at 53 MeV is determined.

T2K est une expérience de neutrinos à longue ligne de base à base d'accélérateurs au Japon. Le but principal de l'expérience T2K est la recherche d'une violation de la PC dans le secteur du lepton en mesurant l'apparence (anti)neutrino des électrons dans un faisceau muon (anti)neutrino. Le flux (anti) neutrino initial est produit par les désintégrations des hadrons qui proviennent des interactions et des ré-interactions d'un faisceau de protons de 30 GeV avec une cible en graphite de 90 cm de long. La connaissance du flux de neutrinos T2K est limitée en raison des grandes incertitudes liées à la production de hadrons. Une série de mesures de production d'hadrons a été effectuée pour résoudre ce problème, dans l'expérience NA61/SHINE au CERN. Les mesures ont été effectuées avec un faisceau de protons et deux types de cibles : une cible en graphite mince et une réplique de la cible T2K. Les travaux présentés dans cette thèse se concentrent sur les données cibles de la réplique T2K prises en 2010 et sur le développement du logiciel d'analyse et d'étalonnage. Le but de ces mesures est de contraindre complètement la production de π+, π+, π-, K+, K+, K- et p provenant de la surface cible en mesurant les rendements différentiels en hadrons dans les cellules du momentum de particules sortant (p), l'angle polaire (θ) et la position longitudinale sur la surface cible (z). Cela permettra de réduire les incertitudes du flux de neutrinos T2K d'environ 10 % à moins de 5 %. Les prédictions de Fluka2011.2c.5 Les listes de physique Monte Carlo, NuBeam et QGSP_BERT de Geant4.10.03 ont été comparées aux données et il a été constaté que Fluka2011.c2.5 donne la meilleure prévision. / T2K is an accelerator-based long-baseline neutrino experiment in Japan. The main goal of the T2K experiment is a search for CP violation in the lepton sector by measuring electron (anti) neutrino appearance in a muon (anti)neutrino beam. Initial (anti) neutrino flux is produced in decays of hadrons which originate from the interactions and the re-interactions of a 30 GeV proton beam with a 90 cm long graphite target. Knowledge of the T2K neutrino flux is limited due to large hadron production uncertainties. A series of hadron production measurements were done to solve this problem, in the NA61/SHINE experiment at CERN. Measurements were performed with a proton beam and two target types: a thin graphite target and a replica of the T2K target. Work presented in this thesis concentrates on the T2K replica target data taken in 2010 and the development of the analysis and calibration software. The aim of these measurements is to fully constrain production of π+ , π− , K+ , K− and p coming from the target surface by measuring differential hadron yields in the bins of outgoing particle momentum (p), polar angle (θ) and longitudinal position on the target surface (z). This will allow reduction of the T2K neutrino flux uncertainties from around 10% to below 5%. Predictions of Fluka2011.2c.5 Monte Carlo, NuBeam and QGSP_BERT physics lists from Geant4.10.03 have been compared to the data and it has been found that Fluka2011.c2.5 gives the best prediction.

abstract: For this project, the diffuse supernova neutrino background (DSNB) has been calculated based on the recent direct supernova rate measurements and neutrino spectrum from SN1987A. The estimated diffuse electron antineutrino flux is ∼ 0.10 – 0.59 /cm2/s at 99% confidence level, which is 5 times lower than the Super-Kamiokande 2012 upper limit of 3.0 /cm2/s, above energy threshold of 17.3 MeV. With a Megaton scale water detector, 40 events could be detected above the threshold per year. In addition, the detectability of neutrino bursts from direct black hole forming collapses (failed supernovae) at Megaton detectors is calculated. These neutrino bursts are energetic and with short time duration, ∼ 1s. They could be identified by the time coincidence of N ≥2 or N ≥3 events within 1s time window from nearby (4 – 5 Mpc) failed supernovae. The detection rate of these neutrino bursts could get up to one per decade. This is a realistic way to detect a failed supernova and gives a promising method for studying the physics of direct black hole formation mechanism. Finally, the absorption of ultra high energy (UHE) neutrinos by the cosmic neutrino background, with full inclusion of the effect of the thermal distribution of the background on the resonant annihilation channel, is discussed. Results are applied to serval models of UHE neutrino sources. Suppression effects are strong for sources that extend beyond z ∼ 10. This provides a fascinating probe of the physics of the relic neutrino background in the unexplored redshift interval z ∼ 10 – 100. Ultimately this research will examine the detectability of DSNB, neutrino bursts from failed supernovae and absorption effects in the neutrino spectrum. / Dissertation/Thesis / Ph.D. Physics 2013