Particle acoustic detection in gravitational wave aluminum resonant antennas

TL;DR

This study investigates particle-induced acoustic signals in aluminum resonant antennas at cryogenic temperatures, demonstrating agreement with theoretical models and advancing understanding of cosmic ray detection via gravitational wave detectors.

Contribution

It presents experimental measurements of particle-induced vibrations in aluminum resonant bars at low temperatures, confirming theoretical predictions and improving detection models.

Findings

Vibrations measured match model predictions within 10%

Acoustic signals are detectable down to 4 K

Results support use of aluminum resonant bars for cosmic ray detection

Abstract

The results on cosmic rays detected by the gravitational antenna NAUTILUS have motivated an experiment (RAP) based on a suspended cylindrical bar, which is made of the same aluminum alloy as NAUTILUS and is exposed to a high energy electron beam. Mechanical vibrations originate from the local thermal expansion caused by warming up due to the energy lost by particles crossing the material. The aim of the experiment is to measure the amplitude of the fundamental longitudinal vibration at different temperatures. We report on the results obtained down to a temperature of about 4 K, which agree at the level of about 10% with the predictions of the model describing the underlying physical process.