Design of the magnetic diagnostics unit onboard LISA Pathfinder

TL;DR

This paper details the design of the magnetic diagnostics unit for LISA Pathfinder, a mission testing technologies for space-based gravitational wave detection, focusing on measuring magnetic effects on test masses with high accuracy.

Contribution

It presents a novel design approach for the magnetic diagnostics unit capable of accurately assessing magnetic properties of test masses in space.

Findings

Achieved the desired measurement accuracy for magnetic properties.

Demonstrated the effectiveness of the diagnostics unit in a space environment.

Enhanced understanding of magnetic disturbances affecting gravitational wave measurements.

Abstract

LISA (Laser Interferometer Space Antenna) is a joint mission of ESA and NASA which aims to be the first space-borne gravita- tional wave observatory. Due to the high complexity and technological challenges that LISA will face, ESA decided to launch a technological demonstrator, LISA Pathfinder. The payload of LISA Pathfinder is the so-called LISA Technology Package, and will be the highest sensitivity geodesic explorer flown to date. The LISA Technology Package is designed to measure relative accelerations between two test masses in nominal free fall (geodesic motion). The magnetic, thermal and radiation disturbances affecting the payload are monitored and dealt by the diagnostics subsystem. The diagnostics subsystem consists of several modules, and one of these is the magnetic diagnostics unit. Its main function is the assessment of differential acceleration noise between test masses due to the magnetic effects. To do so, it has to determine the magnetic characteristics of the test masses, namely their magnetic remanences and susceptibilities. In this paper we show how this can be achieved to the desired accuracy.