A Search for Astrophysical Ultra High Energy Neutrinos with the ANITA-IV Experiment

• Main Author: Cao, Peng
• Format: Thesis
• Language: English
• Published: University of Delaware 2018
• Subjects: Astrophysics; Antarctic; The Antarctic; Antarc*; Antarctica
• Online Access: http://pqdtopen.proquest.com/#viewpdf?dispub=13425957

The Antarctic Impulsive Transient Antenna (ANITA) is a balloon-based experiment designed to search for ultra-high energy(UHE) neutrinos and cosmic rays in Antarctica. A successful detection would be an important step in understanding the most energetic cosmic accelerators in the universe. The fourth flight of ANITA (ANITA-IV) funded by NASA took place in December 2016. It uses a radio antenna array designed to detect Askaryan radiation from UHE neutrino-induced showers in ice and geomagnetic radiation from Extensive Air Showers (EAS) induced by cosmic rays. In this dissertation, I present my analysis of the ANITA-IV flight data with the objective to search for ultra-high energy neutrino and cosmic ray events. The data analysis includes six major aspects: instrument calibrations, event direction reconstruction, event quality cuts, thermal events cut, anthropogenic events cut (clustering), and background estimation. Twenty-four cosmic ray candidates and one neutrino candidate events were found each with an estimated background of 0.34 event. Although the signal significance for a single neutrino event is consistent with background, it still leads to the world's best limit on the ultra-high energy neutrino flux for energy above 4 × 10 19 eV.