Effect of energy deposited by cosmic-ray particles on interferometric gravitational wave detectors

TL;DR

This paper analyzes how cosmic-ray particles deposit heat in interferometric gravitational wave detectors, affecting their noise levels, and compares responses in different detector types, concluding that cosmic-ray impacts are generally below detection thresholds.

Contribution

It derives a general formula for mirror response to cosmic-ray passage and compares cosmic-ray effects across interferometric and resonant detectors, highlighting their differences.

Findings

Cosmic-ray induced vibrations are below future detector sensitivity.

High-energy cosmic-ray muons are rare, arriving once per millennium.

The response formula aids in understanding cosmic-ray noise in detectors.

Abstract

We investigated the noise of interferometric gravitational wave detectors due to heat energy deposited by cosmic-ray particles. We derived a general formula that describes the response of a mirror against a cosmic-ray passage. We found that there are differences in the comic-ray responses (the dependence of temperature and cosmic-ray track position) in cases of interferometric and resonant gravitational wave detectors. The power spectral density of vibrations caused by low-energy secondary muons is 100-times smaller than the goal sensitivity of future second-generation interferometer projects, such as LCGT and Advanced LIGO. The arrival frequency of high-energy cosmic-ray muons that generate enough large showers inside mirrors of LCGT and Advanced LIGO is one per a millennium. We also discuss the probability of exotic-particle detection with interferometers.