Notes about Noise in Gravitational Wave Antennas Created by Cosmic Rays

TL;DR

This paper investigates how cosmic ray-induced thermal fluctuations in mirror coatings can create noise in gravitational wave detectors, potentially exceeding volume fluctuation effects and impacting detector sensitivity.

Contribution

It introduces an analysis of surface thermal expansion effects caused by cosmic rays, highlighting their significance in gravitational wave antenna noise modeling.

Findings

Surface fluctuations from coating thermal expansion can surpass volume effects.

Cosmic rays may significantly contribute to mirror surface noise.

Implications for improving gravitational wave detector sensitivity.

Abstract

Thermodynamical fluctuations of temperature in mirrors may produce surface fluctuations not only through thermal expansion in mirror body but also through thermal expansion in mirror coating. We analyze the last "surface" effect which can be larger than the first "volume" one due to larger thermal expansion coefficient of coating material and smaller effective volume. In particular, these fluctuations may be important in laser interferometric gravitational antennae.