Acoustic Studies for the KM3NeT deep-sea Neutrino Telescope

The KM3NeT collaboration is constructing two large neutrino detectors in the Mediterranean Sea: ARCA, located near Sicily and aimed at neutrino astronomy, and ORCA, located near Toulon and designed for neutrino oscillation studies. The two detectors will have hundreds of Detection Units (DUs) with 18 Digital Optical Modules (DOMs) maintained vertical by buoyancy, forming a large 3D optical array for detecting the Cherenkov light produced after the neutrino interactions. To properly reconstruct the direction of the incoming neutrino, the position of the DOMs must be known with an accuracy of less than 10 cm. For this purpose, KM3NeT has implemented an Acoustic Positioning System (with emitters spread over the seabed, and receivers at each DU base and DOM, to get the DOMs position) and accelero-magnetic sensors for the DOMs orientation. The acoustic receivers of the DU bases have a higher sensitivity than those of the DOMs and remain fixed. Both characteristics offer a wide range of acoustic possibilities: bioacoustics studies, ship noise monitoring, environmental noise assessment, acoustic neutrino detection, etc. This presentation shows the need to calibrate them and a possible analysis to develop a future acoustic detector of ultra-high-energy neutrinos.

Authors: Dídac D.Tortosa (presenter); Miguel Ardid; Juan A. Martínez-Mora; Manuel Bou-Cabo; Guillermo F. Lara-Martínez; Carlos D. Llorens-Álvarez; Víctor Espinosa