Localizing Gravitational Wave Sources with Single-Baseline Atom Interferometers

TL;DR

This paper demonstrates that mid-frequency band atom interferometer detectors, even with a single baseline, can effectively localize gravitational wave sources by leveraging orbital motion, enhancing multi-messenger astronomy.

Contribution

It introduces the concept that single-baseline atom interferometers in the mid-frequency band can localize sources through Doppler shifts caused by orbital motion, providing a new approach for gravitational wave astronomy.

Findings

Mid-frequency band (0.03-10 Hz) is effective for source localization.

Single-baseline atom interferometers can achieve accurate sky localization.

Orbital motion enhances localization capability similar to multiple detectors.

Abstract

Localizing sources on the sky is crucial for realizing the full potential of gravitational waves for astronomy, astrophysics, and cosmology. We show that the mid-frequency band, roughly 0.03 to 10 Hz, has significant potential for angular localization. The angular location is measured through the changing Doppler shift as the detector orbits the Sun. This band maximizes the effect since these are the highest frequencies in which sources live several months. Atom interferometer detectors can observe in the mid-frequency band, and even with just a single baseline can exploit this effect for sensitive angular localization. The single baseline orbits around the Earth and the Sun, causing it to reorient and change position significantly during the lifetime of the source, and making it similar to having multiple baselines/detectors. For example, atomic detectors could predict the location of upcoming black hole or neutron star merger events with sufficient accuracy to allow optical and other electromagnetic telescopes to observe these events simultaneously. Thus, mid-band atomic detectors are complementary to other gravitational wave detectors and will help complete the observation of a broad range of the gravitational spectrum.