Dissertation
Characterization of time-varying backgrounds in the PROSPECT experiment
Doctor of Philosophy (Ph.D.), Drexel University
Mar 2021
DOI:
https://doi.org/10.17918/00000567
Abstract
Recent reactor neutrino experiments aimed for the study of neutrino oscillations exhibited anomalies in both flux and the antineutrino spectrum. The ~6% defficiency of observed flux with respect to theoretical predictions, called the Reactor Antineutrino Anomaly, can be explained through flaws in theoretical model of reactor antineutrino spectrum or existence of eV-scale sterile neutrino state leading to meter-scale neutrino oscillations. The anomaly in spectrum in the energies 4-6 MeV raised a question about insufficiency of our reactor nuclear model. The Precision Reactor Oscillation and Spectrum Experiment (PROSPECT) was developed to study these anomalies by looking at antineutrino oscillations at short (<12 m) baselines from a highly-enriched (~ 93% 235U) uranium reactor core. The detector precisely measured and compared the 235U antineutrino spectrum to the existing nuclear data and performed a reactor-model independent search for eV-scale sterile neutrino oscillations, extending current parameter map of sterile neutrinos. The major challenge of the PROSPECT experiment is distinguishing the rare neutrino signal from a very high background rate on the surface. One of the strategies that PROSPECT utilizes for this is a background subtraction - a bin-by-bin energy spectrum subtraction when the reactor is shut down from when the reactor is operating. This work discusses the background measurements of PROSPECT detector, attributing the time variation of the background to the environmental parameters, evolution of the detector, and the operation status of the reactor, and presents details of successful handling of the background subtraction.
Metrics
69 File views/ downloads
62 Record Views
Details
- Title
- Characterization of time-varying backgrounds in the PROSPECT experiment
- Creators
- Olga Kyzylova
- Contributors
- Michelle Dolinski (Advisor)
- Awarding Institution
- Drexel University
- Degree Awarded
- Doctor of Philosophy (Ph.D.)
- Publisher
- Drexel University; Philadelphia, Pennsylvania
- Number of pages
- xvi, 134 pages
- Resource Type
- Dissertation
- Language
- English
- Academic Unit
- College of Arts and Sciences; Physics; Drexel University
- Other Identifier
- 991014962647304721