First results on angular response and efficiency of acoustic sensors of the South Pole Acoustic Test Setup

摘要

The South Pole Acoustic Test Setup consists of four strings, each instrumented with seven acoustic sensors and transmitters frozen in the upper 500 m of the South Pole glacial ice. SPATS sensors have been extensively studied in the laboratory at changing temperatures and pressure in air, water and ice. It was however impossible to create conditions like in deep ice at the South Pole. We present here different methods to investigate angular response and efficiency of the acoustic sensors after deployment. The corresponding results are used to discuss the reliability of SPATS detector measurements. We conclude with an outlook on the applicability of the described methods to future acoustic or hybrid detectors for the detection of cosmic neutrinos in ice.