Second generation instruments for the Laser Interferometer Gravitational Wave Observatory (LIGO)

TL;DR

This paper discusses the design, technology, and projected sensitivity of second-generation LIGO interferometers, which aim to significantly improve gravitational wave detection capabilities across a broader frequency range.

Contribution

It introduces new interferometer designs for second-generation LIGO, detailing their physics, technology, and expected sensitivity improvements over previous detectors.

Findings

Projected sensitivity spectra show significant improvements.

Potential for increased detection volume and lower frequency observations.

Design considerations for narrowband performance.

Abstract

The interferometers being planned for second generation LIGO promise and order of magnitude increase in broadband strain sensitivity--with the corresponding cubic increase in detection volume--and an extension of the observation band to lower frequencies. In addition, one of the interferometers may be designed for narrowband performance, giving further improved sensitivity over roughly an octave band above a few hundred Hertz. This article discusses the physics and technology of these new interferometer designs, and presents their projected sensitivity spectra.