Testing of the Triggering Interferometric Sum Correlator and the Tunable Universal Filtering Frontend

Abstract

The Antarctic Impulsive Transient Antenna (ANITA) is a balloon-borne radio experiment that is designed to detect ultra-high energy (UHE) neutrinos and cosmic rays. The fourth iteration of ANITA is currently flying and was launched on December 2, 2016 in Antarctica. ANITA 4 will fly for twenty to forty-five days at heights that range from thirty-five to forty kilometers. After ascending to these altitudes, ANITA 4 observes the ice below it for radio pulses that are a result of neutrino interactions with the ice. During the summer, two of the main components of the ANITA 4 data acquisition system were worked on at Ohio State University (OSU). These components were the Triggering Interferometric Sum Correlator (TISC) and the Tunable Universal Filtering Frontend (TUFF). The TISC was designed to make the ANITA 4 triggering system more efficient and able to observe more frequent, low-energy events. The TUFF was designed to block out certain continuous wave frequencies. The TUFFs were assembled and then the hardware problems were debugged and fixed for both circuit boards. Different software was required for each board to help calibrate the various components while also ensuring that they communicate correctly with the rest of ANITA 4. The boards were also tested in environments similar to where ANITA 4 is currently flying. While testing the TISC, it was found that some of the components, such as the Field Programmable Gate Arrays, did not work correctly. This problem caused specific bits to be inverted or locked into a state. This in turn made the TISC not perform correctly and unusable for ANITA 4. The TUFF was assembled and modified based on tests and is currently onboard ANITA 4. The TUFF will hopefully allow ANITA 4 to obtain more data about cosmic rays and UHE neutrino interactions during its flight.