Gravity gradient suppression in spaceborne atomic tests of the equivalence principle

TL;DR

This paper presents a method using gravity inversion and modulation with a gimbal mount to suppress gravity gradient effects in spaceborne atomic tests of the equivalence principle, enhancing measurement accuracy.

Contribution

It introduces a novel technique for gravity gradient suppression in atomic EP tests, reducing systematic errors without requiring overlapping atomic species.

Findings

Gravity gradient effects can be significantly suppressed using the proposed method.

The technique reduces the need for overlapping atomic species in experiments.

Systematic errors due to gravity gradients are minimized in spaceborne atomic tests.

Abstract

The gravity gradient is one of the most serious systematic effects in atomic tests of the equivalence principle (EP). While differential acceleration measurements performed with different atomic species under free fall test the validity of EP, minute displacements between the test masses in a gravity gradient produces a false EP-violating signal that limits the precision of the test. We show that gravity inversion and modulation using a gimbal mount can suppress the systematics due to gravity gradients caused by both moving and stationary parts of the instrument as well as the environment, strongly reducing the need to overlap two species.