Status and recent results of the South Pole Acoustic Test Setup

TL;DR

The South Pole Acoustic Test Setup (SPATS) has been operational since 2007, successfully measuring ice acoustic properties relevant for neutrino detection, providing crucial data for future Antarctic acoustic neutrino observatories.

Contribution

This paper reports the latest results of SPATS, demonstrating its success in measuring key ice acoustic parameters for neutrino detection in Antarctica.

Findings

Measured sound speed and its depth dependence

Determined attenuation length and noise levels

Characterized transient background sources

Abstract

The South Pole Acoustic Test Setup (SPATS) has been deployed to study the feasibility of acoustic neutrino detection in Antarctic ice around the South Pole. An array of four strings equipped with acoustic receivers and transmitters, permanently installed in the upper 500 m of boreholes drilled for the IceCube neutrino observatory, and a retrievable transmitter that can be used in the water filled holes before the installation of the IceCube optical strings are used to measure the ice acoustic properties. These include the sound speed and its depth dependence, the attenuation length, the noise level, and the rate and nature of transient background sources in the relevant frequency range from 10 kHz to 100 kHz. SPATS is operating successfully since January 2007 and has been able to either measure or constrain all parameters. We present the latest results of SPATS and discuss their implications for future acoustic neutrino detection activities in Antarctica.