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The beta dose distributions in red bone marrow equivalent material due to imbedded continuous sources were measured experimentally with ultra thin LiF thermoluminescent dosimeters near planar interfaces of cortical bone (CB) and red bone marrow (RBM), and RBM and air. It has been also investigated numerically by Cyltran, the Monte Carlo code. In the Monte Carlo approach, the dose enhancement ratio for a planar CB-RBM interface increases with electron energy and reaches a plateau at 0.50 MeV while the dose reduction ratio for a planar vacuum-RBM interface decreases to a steady value from 1.00 MeV onwards. With a semi-infinite source of 32P, dose enhancement ratios at 0-9, 79-88, and 157-166 mg/cm2 separations from a planar CB-RBM interface were measured to be 1.07±0.01, 1.03+0.03 and 0.99+0.03 respectively. The dose reduction ratios at these separations from a planar AIR-RBM interface were found to be 0.82±0.01, 0.94+0.03 and 0.97+0.03 respectively. Both the dose enhancement ratios and dose reduction ratios agree with the results calculated by the Monte Carlo approach within one standard deviation except for the dose reduction ratio at 0-9 mg/cm2 from the AIR-RBM interface. The experimental result in this case is about three standard deviations less than the Monte Carlo results. Using the same Monte Carlo code, the dose enhancement ratio at 0-20 micron separation from a planar CB-RBM interface due to a point or plane source of 0.50 MeV electrons at the interface reaches saturation at approximately 0.22 times the CSDA range of 0.5 MeV electron in CB for both plane and point source configurations. The saturation dose enhancement ratio for both configurations is 1.06±0.01. / Thesis / Master of Science (MS)

The auroral oval is a region of intense Global Navigation Satellite System (GNSS) radio scintillation. Ionospheric turbulence can cause scintillation below 3 GHz which means it can severely affect Global Positioning System (GPS) and other forms of wireless communication such as radio frequency (RF) and ultrahigh frequency (UHF). These effects are particularly prevalent at high latitudes, where auroral ionization patterns affect signals and low latitudes where plasma instabilities structure the ionosphere to small scales. This thesis addresses the connection between a well-known GPS derived measurement called total electron content (TEC) to ionospheric state parameters through optical imaging and modeling. The first part of this thesis uses the Global Airglow (GLOW) aeronomical model to infer height-dependent ionospheric state parameters. Spectral imagery and GNSS data are combined to constrain the state outputs of GLOW using a Nelder-Mead optimization during periods of auroral-induced scintillation. The second part of the thesis models the ionospheric continuity equation to produce high-rate electron temperature estimates using temperature dependent recombination from a combined optical and GNSS perspective. Both of these methods quantify E-region dynamic state parameters at a rate (<10 second) that is unachievable by any standard means, such as incoherent scatter radar (ISR). The reliability of these methods is contextualized for the E-region response to auroral forcing for coaligned and non-ideal measurement scenarios common in high latitude receiver networks.

In recent years, many high precision experiments were carried aiming to improve the accuracy on the measurements of the neutrino oscillation parameters. One of the main source of uncertainty for neutrino oscillation experiments is due to the lack of a comprehensive theoretical description of neutrino-nucleus interactions. The US Deep Underground Neutrino Oscillation Experiments (DUNE) will deploy a series of detectors using Liquid Argon Time Projection Chambers (LArTPCs). A fully consistent parameter-free theoretical neutrino-nucleus scattering model on argon does not exist. The first step towards constructing a nuclear model will be to determine the energy and momentum distribution of protons and neutrons inside the argon nucleus. The JLab E12-14-012 experiment performed at Jefferson Laboratory in Newport News, Virginia, ran in 2017 and will provide such measurements in Argon and Titanium using electron scattering (e,e'p). The data collected by the experiment covers a wide range of energy transfers and also includes several other targets like aluminum and carbon. This Ph.D. thesis will present details of the JLab E12-14-012 experiment, together with first data analysis results of the exclusive (e,e'p) data on Argon and Titanium. / Doctor of Philosophy / Neutrino, a tiny, nearly massless particle was discovered about one hundred years ago. Neutrinos are everywhere around us. If you put your hands under the sunlight, each second, there will be about one billion neutrinos pass through them. As the second most abundant particle in the universe, it is extremely important to study neutrinos as they affect many fundamental aspects of our lives. For examples, neutrinos could help us study the nucleons' structure, and how the matter evolved from one particle to many. Since neutrinos are produced in nuclear fusion processes from the sun and stars, we could also understand the sun and universe better by studying the property of neutrinos. Neutrinos have three flavors, and they could change flavors through neutrino oscillation. Measuring the neutrino oscillation parameters is one of the priority tasks for the physics society. Lots of experiments were carried aiming to enhance the understanding of neutrinos and improve the neutrino oscillation measurements accuracy. The most exciting and famous one is the Deep Underground Neutrino Experiment (DUNE) that will be carried in Fermilab. DUNE is an accelerator based experiment that will use Argon as the neutrino target to study the neutrino oscillation. In order to improve the measurement accuracy of the oscillation parameters for the DUNE, a well defined theoretical model for neutrino interaction on Argon is needed. Thus, the JLab E12-14-012 experiment was performed in Hall A at Jefferson Lab in Newport, News, VA to help people get ready for this through electron scattering. The primary goal of this experiment is to measure the electron-nucleus interaction through (e,e$^\prime$p) reactions and further develop a electron-nucleus model to be used in the future neutrino experiments. This thesis will present an overview of the experimental setup and results from the data analysis.