MICROSCOPE: systematic errors

TL;DR

This paper discusses the identification and evaluation of systematic errors affecting the MICROSCOPE mission's test of the Weak Equivalence Principle, aiming for unprecedented precision in orbit.

Contribution

It provides a comprehensive analysis and bounding of various systematic error sources to ensure reliable WEP measurement accuracy.

Findings

Systematic errors are categorized into external, design-related, and internal sources.

Each error source is evaluated or bounded to set an upper limit on WEP measurement uncertainty.

The analysis supports achieving the mission's high-precision goals.

Abstract

The MICROSCOPE mission aims to test the Weak Equivalence Principle (WEP) in orbit with an unprecedented precision of 10$^{-15}$ on the E\"otv\"os parameter thanks to electrostatic accelerometers on board a drag-free micro-satellite. The precision of the test is determined by statistical errors, due to the environment and instrument noises, and by systematic errors to which this paper is devoted. Systematic error sources can be divided into three categories: external perturbations, such as the residual atmospheric drag or the gravity gradient at the satellite altitude, perturbations linked to the satellite design, such as thermal or magnetic perturbations, and perturbations from the instrument internal sources. Each systematic error is evaluated or bounded in order to set a reliable upper bound on the WEP parameter estimation uncertainty.