Interferometer Response to Scalar Gravitational Waves

TL;DR

This paper analyzes how scalar gravitational waves from scalar-tensor theories affect interferometer responses, focusing on magnetic components and frequency-dependent behaviors for ground and space-based detectors.

Contribution

It extends previous work by deriving the response function for scalar GWs' magnetic component and discusses angular dependence and high-frequency behavior.

Findings

Magnetic component significantly influences response functions.

Response functions depend on the angular orientation of the interferometer.

Proper distance calculations are relevant for high-frequency space-based detectors.

Abstract

It was recently suggested that the magnetic component of Gravitational Waves (GWs) is relevant in the evaluation of frequency response functions of gravitational interferometers. In this paper we extend the analysis to the magnetic component of the scalar mode of GWs which arise from scalar-tensor gravity theory. In the low-frequency approximation, the response function of ground-based interferometers is calculated. The angular dependence of the electric and magnetic contributions to the response function is discussed. Finally, for an arbitrary frequency range, the proper distance between two test masses is calculated and its usefulness in the high-frequency limit for space-based interferometers is briefly considered.