Wideband dual sphere detector of gravitational waves

TL;DR

This paper proposes a novel broadband resonant mass gravitational wave detector using a dual sphere setup with optical readout, achieving high sensitivity at cryogenic temperatures in the 1000-3000 Hz range.

Contribution

It introduces a new design for a broadband gravitational wave detector employing a dual sphere configuration with optical readout, reaching near quantum-limited sensitivity.

Findings

Spectral strain sensitivity of 2x10^-23/√Hz between 1000 Hz and 3000 Hz.

Design achieves near quantum-limited sensitivity at cryogenic temperatures.

Size of the detector is approximately 2 meters.

Abstract

We present the concept of a sensitive AND broadband resonant mass gravitational wave detector. A massive sphere is suspended inside a second hollow one. Short, high-finesse Fabry-Perot optical cavities read out the differential displacements of the two spheres as their quadrupole modes are excited. At cryogenic temperatures one approaches the Standard Quantum Limit for broadband operation with reasonable choices for the cavity finesses and the intracavity light power. A molybdenum detector of overall size of 2 m, would reach spectral strain sensitivities of 2x10^-23/Sqrt{Hz} between 1000 Hz and 3000 Hz.