Vibration Isolation for the Laser Interferometer Lunar Antenna

TL;DR

This paper discusses the design of vibration isolation suspensions for the Lunar Antenna (LILA), a gravitational wave detector concept that operates at sub-Hertz frequencies on the Moon, filling a gap between space and Earth-based detectors.

Contribution

It introduces baseline suspension designs for LILA, considering different lunar seismic conditions, advancing the feasibility of lunar gravitational wave detection.

Findings

Baseline suspension designs for LILA Horizon proposed.

Seismic background assumptions influence suspension design.

LILA's sub-Hertz detection capability is feasible with proper isolation.

Abstract

The Laser Interferometer Lunar Antenna (LILA) presents a novel concept for observing gravitational waves from astrophysical sources at sub-Hertz frequencies. Compared to the Earth, the seismic environment of the moon, while uncertain, is known to be orders of magnitude lower, opening the possibility for achieving this sub-Hz band. This band fills the gap between space-based detectors (mHz) and Earth-based detectors (10 Hz to a few kHz). The initial version of LILA, known as LILA Pioneer, calls for non-suspended optics, relying on the moon's resonant modes to respond to gravitational waves. However, the follow-on design, LILA Horizon, requires suspensions to realize in-band free floating test masses and to filter the residual seismic background. This paper will establish baseline designs for these suspensions for different assumptions of the seismic background.