Response of the common mode of interferometric detectors to a stochastic background of massive scalar radiation

TL;DR

This paper analyzes how the common mode of interferometric detectors responds to a stochastic massive scalar background, revealing that common modes may have higher cross-correlation responses than differential modes for non-relativistic backgrounds.

Contribution

It provides the first detailed calculation of the angular pattern and overlap reduction functions for the common mode response to massive scalar backgrounds.

Findings

Common modes can have higher cross-correlation responses than differential modes for non-relativistic backgrounds.

Overlap between common and differential modes is discussed, indicating potential for improved detection strategies.

Response functions depend on the mass and velocity distribution of the scalar background.

Abstract

We compute the angular pattern and the overlap reduction functions for the geodesic and non-geodesic response of the common mode of two interferometers interacting with a stochastic, massive scalar background. We also discuss the possible overlap between common and differential modes. We find that the cross-correlated response of two common modes to a non-relativistic background may be higher than the response of two differential modes to the same background.