Characterization of a fiber laser hydrophone for acoustic neutrino detection

TL;DR

This paper introduces a fiber laser hydrophone optimized for deep-sea acoustic neutrino detection, demonstrating its reliable performance under high-pressure conditions and low-noise environments through laboratory and basin tests.

Contribution

It presents a novel fiber laser hydrophone design with static pressure compensation suitable for deep-sea neutrino detection applications.

Findings

Maintains sensitivity after 140-bar pressure cycling

Resonance peaks identified in low- and high-frequency ranges

Sensitivity aligns with ambient sea noise levels

Abstract

This paper presents the development and characterization of a fiber laser hydrophone designed for deep-sea applications, with a focus on detecting neutrino interactions via their acoustic signatures. The hydrophone design includes a static pressure compensation mechanism, ensuring reliable operation at depths exceeding 1 km. The performance of the hydrophone was evaluated through laboratory tests and experiments in an anechoic basin, where its transfer function was measured before and after a 140-bar pressure cycle. The results show that the hydrophone maintains its sensitivity, with resonance peaks identified in both low- and high-frequency ranges. The hydrophone's sensitivity to acoustic signals was also compared to ambient sea state noise levels, demonstrating compatibility with the lowest noise conditions.