The Acoustic Detection System of the ANTARES Neutrino Telescope in the Mediterranean Sea

The ANTARES Neutrino Telescope is a water Cherenkov detector currently under construction in the Mediterranean Sea at a water depth of roughly 2500 m and scheduled for completion in the first quarter of 2008. Furthermore, the detector serves as a platform for investigations of the deep sea environment. In this context, acoustic sensors will be integrated into the infrastructure of the experiment. The main goal is to investigate the method of acoustic detection for neutrinos, which utilises the effect that a particle shower evolving from a neutrino interaction in water at very high energies generates a detectable pressure pulse. For these investigations, tests of acoustic particle detection techniques and deep sea acoustic background studies will be performed while the system is also well suited to study marine life in the Mediterranean Sea. The acoustic detection setup will comprise 6 clusters consisting of 6 acoustic sensors each. The clusters are distributed over the ANTARES detector with inter-spacings ranging from about 10 m to roughly 100 m vertically and 200 m horizontally to allow position reconstruction of point sources at different length scales. Working with a standard sampling rate of 250 k SPS, 16- bit digitisation and an optional, stepwise amplification factor from 1 to 562, the system is designed to have a dynamic range of about 3 mPa to 10 Pa (RMS) for a frequency range of about 1 kHz to 100 kHz.