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

In the first part of the thesis we explore the sensitivity to sterile neutrinos by using a novel kaon tagging technology: ENUBET, the proposed experiment could decisively test indications from the experiments Neutrino-4 and IceCube. In the second part of the thesis we discuss the current status of sterile neutrino searches at nuclear reactors, we present a study with the optimization of a green field, two baseline reactor experiment with respect to the sensitivity for electron anti-neutrino disappearance in search of a light sterile neutrino at both research and commercial reactors. We find that a total of 5 tons of detectors deployed at a commercial reactor with a closest approach of 25 m can probe the mixing angle sin²2θ down to ∼ 5 × 10⁻³ around ∆m² ∼ 1 eV² . The same detector mass deployed at a research reactor can be sensitive up to ∆m² ∼ 20 − 30 eV² assuming a closest approach of 3 m and excellent energy resolution, such as that projected for TAO. We also find that lithium doping of the reactor could be effective in increasing the sensitivity for higher ∆m² values. / Master of Science / A sterile neutrino is a particle that is not included in the actual content of matter at the fundamental level. Our goal in this thesis was to search for an imprint of this particle at neutrino experiments. We performed numerical simulations using the experimental specification given in the literature to predict what this signal should look like. The importance of searching for this particle arises from indications at neutrino nuclear experiments, if this particle exists, that would imply new physics beyond our actual understanding of the matter content in the universe. The first search was performed at an experimental facility called ENUBET and the second search was performed at nuclear reactors. Testing this elusive particle means we need to determine two parameters from a model. The results of the aforementioned parameter space searches are presented in this thesis. The statistical significance in our findings is not entirely conclusive to either confirm or refute the sterile neutrino. The benefits of studying neutrinos at nuclear reactors is that they are produced in generating electrical power as well as monitoring nuclear weapons.

Class of 2011 Abstact / OBJECTIVES: To determine if aseptic methods prescribed by the USP 797 are effective in preventing microbial growth when compounding intravenous medication. Sample size: 60 individual IV preparations, 20 for the control group and 20 per test group. METHODS: Sixty agar plates were made. The IV preparations for the control group were compounded with aseptic technique: washing hands with soap and water, wearing gloves, cleaning all ports with alcohol, and working in a laminar flow hood. A syringe was used to inject the water from the vial into the IV bag. This procedure was repeated in the same manner for Group A (no use of laminar flow hood) and Group B (no swiping of the injection ports with an alcohol swab), minus the aseptic technique in question. Once all 60 IV preparations were completed, a sterile inoculation tool was used to obtain a sample from the port of the IV bag. The plates were then inoculated. RESULTS: When compared to the control group, microbial growth in Group A was not significant (p=0.14). The contamination rate for Group B was also not significant (p=0.07). CONCLUSION: Solutions compounded using abbreviated techniques (not swabbing injection ports and not using laminar flow hood) are not more likely to be contaminated than when using all proper aseptic techniques simultaneously.

Title: Sterile neutrino physics at NOvA experiment Author: Róbert Králik Institute: Institute of Particle and Nuclear Physics Supervisor: RNDr. Karel Soustružník, Ph.D., Institute of Particle and Nuclear Physics Abstract: NOvA sterile neutrinos search via neutral current (NC) disappearance analysis is moving to a two-detector fit method to be able to fit to a wider range of sterile neutrino oscillations parameters. This introduces among other things a bigger contribution of the neutrino flux systematic uncertainty, which currently makes up the largest overall uncertainty for the ongoing NC disappearance anal- ysis. This thesis focuses on reducing this uncertainty and looks for different ways of making a more precise prediction of the neutrino flux. We point out Horn-Off analysis as the base for doing so and describe the production of a new Horn-Off simulation and the analysis of the Horn-Off results. We were not able to draw any conclusions that would reduce the NC disappearance systematic uncertainty, but the results showed herein can be helpful in the future attempts at a better neutrino flux prediction and a lower neutrino flux systematic uncertainty. Keywords: sterile neutrino neutrino flux NOvA 1

Nanoparticles (NPs) have attracted considerable attention in the field of separation science, especially in filtration studies for direct membrane integrity tests, investigating pore-size distribution, and their potential to be used as surrogates for various types of viruses encountered in water treatment and bioprocessing applications. Although the effect of adding surfactants to stabilize NP suspension have been explored for a number of different applications, there is significant variation in the amounts and types of surfactants used in filtration studies. This study used three different sizes (59, 188, and 490 nm) of fluorescent polystyrene nanoparticles (PNPs) to mimic the length, width, and aggregates of Rhabdovirus Maraba, a bullet-shape envelope virus. The PNPs were suspended in solutions with varying concentrations of the nonionic surfactant Tween 20 (0.0005% to 0.1% (v/v) in the carbonate buffer feed solution) and were tested in constant-flux filtration studies using two commercial microfiltration (MF) membranes (Durapore PVDF and MiniSart PES) with 0.22 micron pore size ratings. Results clearly demonstrate that adding a nonionic surfactant to a PNP solution will cause a shift from full retention to complete transmission during the dead-end MF of PNPs that are smaller than the pore size of an MF membrane. In a separate study, in order to have a better resemblance of virus particles in terms of surface properties, 188 nm PNPs were coated with different (lysozyme, α -lactalbumin and bovine serum albumin) proteins in order to gain similar surface properties to actual virus particles. Filtration results with one type of commercial MF membranes (Durapore PVDF) 0.22 μm pore size, clearly indicate that the transmission behavior of PNPs strongly depends on their surface properties. PNPs fully covered with BSA and α–lactalbumin could completely pass through the membranes while uncovered or partially covered PNPs resulted in no transmission or partial transmission. / Thesis / Master of Applied Science (MASc) / Nanoparticles (NPs) has been employed enormously in various applications for a variety of purposes. One of the areas that have been greatly influenced by NPs, is the field of separation science. In the pharmaceutical industry, purification of therapeutics involves a sequence of filtration and in this step, therapeutic virus filtration, sterile filtration, in particular, have been poorly studied. There is also a growing interest in the use of engineered viruses for cancer treatment due to its magnificent implication on human health. However, there are significant challenges in running filtration experiments with pathogenic substances. Therefore it has been determined that a detailed and comprehensive study of sterile filtration of virus-size NPs can benefit this area. In this work, fluorescently-labeled NPs has been used as surrogates of oncolytic viruses to extract fundamental aspects affecting the transmission of virus-sized particles through commercial microfiltration sterilizing grade membranes.

No description available.

The T2K Experiment is a long-baseline accelerator neutrino oscillation experiment, whose primary aim is to look for ν_e appearance in a ν_μ beam. A predominantly ν_μ beam is produced at J-PARC in Tokai on the east coast of Japan, and neutrino interactions are measured both by a near detector complex, 280 m from the neutrino production target,and by a large water Cerenkov detector, Super-Kamiokande, 295 km away. This thesis is concerned with oscillations ν_μ → ν_e, within both a standard three neutrino model and a model in which there is one additional sterile neutrino. By looking at ν_e appearance over the T2K baseline, this thesis looks for oscil- lations involving one additional sterile neutrino. A region of the short baseline neutrino oscillation parameter space favoured by other experiments is excluded at 3σ. The ND280 is also used to search for ν_e appearance over a short baseline. A ν_e selection is developed, and limits on the short baseline oscillation parameter space are set. Sensitivity predictions are also made for future T2K running. The T2K ND280 is interesting for this work since the detector technology is different to that of other experiments that have seen indications of short baseline electron-neutrino appearance. In the standard three-flavour neutrino oscillation picture, a combined analy- sis of the electron-neutrino appearance results of T2K and another long-baseline accelerator neutrino experiment, MINOS, is presented. Combining the two re- sults with the Feldman-Cousins method results in sin² 2θ₁₃ = 0 being excluded at 2.7σ, assuming the normal neutrino mass hierarchy.

This thesis will present a search for sterile neutrinos using data taken with the MINOS experiment between 2005 and 2012. MINOS is a two-detector on-axis experiment based at Fermilab. The NuMI neutrino beam encounters the MINOS Near Detector 1km downstream of the neutrino-production target before travelling a further 734km through the Earth's crust, to reach the Far Detector located at the Soudan Underground Laboratory in Northern Minnesota. By searching for oscillations driven by a large mass splitting, MINOS is sensitive to the existence of sterile neutrinos through looking for any energy-dependent perturbations using a charged-current sample, as well as looking at any relative deficit in neutral current events between the Far and Near Detectors. This thesis will discuss the novel analysis that enabled a search for sterile neutrinos covering five orders of magnitude in the mass splitting and setting a limit in previously unexplored regions of the sterile neutrino parameter space, where a 3+1-flavour phenomenological model was used to extract parameter limits. The results presented in this thesis are sensitive to the sterile neutrino parameter space suggested by the LSND and MiniBooNE experiments.

No description available.

The violation of baryon number, is an essential ingredient for the preferential creation of matter over antimatter needed to account for the observed baryon asymmetry in the Universe. However, such a process has yet to be experimentally observed. The HIBEAM/NNBAR program is a proposed two-stage experiment at the European Spallation Source to search for baryon number violation. The program will include high-sensitivity searches for processes that violate baryon number by one or two units: free neutron-antineutron oscillation via mixing, neutron-antineutron oscillation via regeneration from a sterile neutron state , and neutron disappearance (n → n′); the effective process of neutron regeneration is also possible. The program can be used to discover and characterize mixing in the neutron, antineutron and sterile neutron sectors. The experiment addresses topical open questions such as the origins of baryogenesis and the nature of dark matter, and is sensitive to scales of new physics substantially in excess of those available at colliders. A goal of the program is to open a discovery window to neutron conversion probabilities (sensitivities) by up to three orders of magnitude compared with previous searches. The opportunity to make such a leap in sensitivity tests should not be squandered. The experiment pulls together a diverse international team of physicists from the particle (collider and low energy) and nuclear physics communities, while also including specialists in neutronics and magnetics.