Speaker: Benjamin Hokanson-Fasig, Physics PhD Graduate Student
Abstract: Neutrinos are unique cosmic messengers that can be used to probe the universe for sources of ultra-high energy cosmic rays. In order to detect the highest energy neutrinos, which are expected to interact very rarely, a large detector volume is necessary. The Askaryan Radio Array (ARA) and similar neutrino detectors use the Antarctic ice as their detector volume, searching for radio signals from neutrino-induced particle showers in the ice. This detection technique results in radio neutrino detectors that are highly sensitive to neutrinos with energies above 10 PeV.
This thesis explores the possibility of using envelopes of the voltage signals from antennas in ARA to perform neutrino searches. A detector making use of signal envelopes could have a significantly lower power consumption, making it an attractive option in power-limited regions like Antarctica. By reproducing the reconstruction method used in previous ARA analyses, a reconstruction using signal envelopes is shown to be able to reconstruct the location of a neutrino event in the ice with an error of 1--2 degrees. However, since the ARA stations are not optimized for this method, the use of signal envelopes for a complete analysis of ARA data is ultimately found to be unrealistic. In the absence of a direct comparison between the previous ARA analysis and a signal-envelope analysis, further applications of the signal envelope are proposed, including detector geometries that are more optimized for envelope analysis as well as options for using signal envelopes to lower the trigger threshold of radio neutrino detectors.