2:00–3:00 pm
Charles Mark Lewis’ PhD Thesis Defense
Thursday, January 19, 2023 at 2:00 pm CST
PARTICLE PHYSICS IN THE SUB-KEV ENERGY REGIME
Coherent elastic neutrino-nucleus scattering (CEvNS) and other rare-event physics searches, like dark matter detection, have been especially furthered by increasing sensitivity to low-energy particle interactions. Experiments using multiple detector technologies have sought CEvNS at the most intense terrestrial sources of neutrinos: spallation facilities and nuclear reactors. I report on the feasibility of using cryogenic pure CsI as an improved next-generation CEvNS target at the up-and-coming European Spallation Source. Calibrations and simulations presented here predict an increase by a factor of at least ~33 in the rate of observable neutrino-induced events per unit mass, compared to past use of room-temperature CsI[Na]. I also report on the first measurement of CEvNS from antineutrinos at the Dresden Generating Station, a power nuclear reactor, employing a large-mass semiconducting germanium diode dubbed NCC-1701. In each section on detecting these neutrino couplings, the importance of understanding device response to low-energy nuclear recoils is highlighted. Finally, finding synergy for tools developed to extricate sub-keV CEvNS signals, I performed a search for the exotic mode of muon decay µ+-> e+X. New sensitivity limits in previously untouched parameter space for a massive boson dark matter candidate of cosmological interest are presented.
Committee Members:
Juan Collar (Chair)
Paolo Privitera
Scott Wakely
Carlos Wagner
Mark will be a postdoc at the DIPC in Donostia-San Sebastián, Gipuzkoa, Spain.