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- Creators: Barrett, The Honors College
Description
Pacemakers in the early 1970s were powered by betavoltaic devices which provided long lasting battery life. The betavoltaic devices also emitted gamma radiation due to inadvertent radioisotope contamination, which could not be completely shielded. The betavoltaic devices were quickly replaced by lithium batteries after their invention, and betavoltaics were abandoned. Modern technological advancements made it possible to isolate beta emitting radioisotopes properly and achieve better energy conversion efficiencies which revived the topic of betavoltaics. This research project has studied state-of-the-art pacemakers and modern radioactive power sources in order to determine if modern pacemakers can be safely nuclear powered and if that is a reasonable combination.
ContributorsAwad, Al-Homam Abdualrahman (Author) / Holbert, Keith (Thesis director) / Aberle, James (Committee member) / Barrett, The Honors College (Contributor) / Electrical Engineering Program (Contributor)
Created2014-12
Description
A search is underway to find baryon resonances that have been predicted, but yet remain unobserved. Nucleon resonances, due to their broad energy widths, overlap and must be disentangled in order to be identified. Meson photoproduction observables related to the orientation of the spin of the incoming photon and the spin of the target proton are useful tools to deconvolve the nucleon resonance spectrum. These observables are particularly sensitive to interference between phases of the complex amplitudes. A set of these observables has been measured using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab with linearly-polarized photons having energies from 725 to 1575 MeV with polar angle values of cos(theta) between -0.8 and 0.9 and transversely-polarized protons in the Jefferson Lab FRozen Spin Target (FROST). By fitting neutron yields from gamma p -> pi^+ n over azimuthal scattering angle, the observables \H and P have been extracted. These observables manifest as azimuthal modulations in the yields for the double-polarization experiment. Preliminary results for these observables will be presented and compared with predictions provided by the SAID Partial-Wave Analysis Facility.
ContributorsLee, Robert John (Author) / Dugger, Michael (Thesis director) / Ritchie, Barry (Committee member) / Department of Physics (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
In nuclear physics, there is a discrepancy between theory and experiment concerning the number of existing nucleon resonances. Current models predict far more states than have been observed. In particular, few searches have found excited nucleon resonances with energies above 2.2 GeV in the K Lambda channel. To investigate high-mass nucleon resonances, efficiency-corrected yields of the reaction ep --> e K+ Lambda(1520) --> e K+ K- p in the center-of-mass energy range 2.1-4.5 GeV are constructed utilizing Jefferson Lab's CLAS12 detector. This paper presents the results of an analysis searching for high-mass nucleon resonances in the K Lambda channel between 2.1-4.5 GeV.
ContributorsOsar, Rebecca (Author) / Dugger, Michael (Thesis director) / Ritchie, Barry (Committee member) / Barrett, The Honors College (Contributor) / Department of Physics (Contributor) / School of International Letters and Cultures (Contributor)
Created2023-05
Description
Different tools have been developed by physicists to detect particle interactions, including one tool called a cloud chamber. A cloud chamber is a device that uses a supersaturated alcohol vapor to outline the paths of subatomic particles. It requires an adequate source of radiation, either background radiation or a radioactive element, that is placed inside the chamber and allowed to decay. The particles emitted from the decaying element form tracks, as a result of the condensation of the supersaturated alcohol. This condensation ionizes the particles as they are being emitted, which creates the visible track. In order to produce curved tracks, which are necessary for data analysis, a suitable magnetic field must also be applied to the moving particles. As these particles come into contact with the magnetic field, their tracks curve, allowing for measurements of the radius of curvature for each track to be deduced. The radius of curvature can then be used to determine the identity of the atomic nucleus that the emitted particle came from. Computer programming can be applied to this process to make it faster and more efficient. This thesis project involved the composition of a software that could control a cloud chamber apparatus set up to view the beta decay of Pb-210 and analyze the tracks produced by emitted electrons to determine their radius of curvature. By the completion of this project, a software was developed that could accurately detect tracks from test images and control several parts of a cloud chamber.
ContributorsBogdanovic, Natalija (Author) / Tucker, Ross (Thesis director) / Solis, Francisco (Committee member) / School of Social and Behavioral Sciences (Contributor) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05