Absolute airborne gravimetry with a cold atom sensor

TL;DR

This paper introduces an absolute airborne gravimeter based on atom interferometry, enabling direct gravity measurements from aircraft with improved accuracy and operational simplicity compared to traditional relative sensors.

Contribution

The work presents the first implementation of an absolute airborne gravimeter using atom interferometry, demonstrating its feasibility and accuracy in real-world conditions.

Findings

Gravity measurement noise of 0.3 mGal on a simulator

Measurement errors between 1.7 and 3.9 mGal in flight

Differences with ground data ranging from -1.9 to 6.2 mGal

Abstract

Measuring gravity from an aircraft is essential in geodesy, geophysics and exploration. Today, only relative sensors are available for airborne gravimetry. This is a major drawback because of the calibration and drift estimation procedures which lead to important operational constraints and measurement errors. Here, we report an absolute airborne gravimeter based on atom interferometry. This instrument has been first tested on a motion simulator leading to gravity measurements noise of 0.3 mGal for 75 s filtering time constant. Then, we realized an airborne campaign across Iceland in April 2017. From a repeated line and crossing points, we obtain gravity measurements with an estimated error between 1.7 and 3.9 mGal. The airborne measurements have also been compared to upward continued ground gravity data and show differences with a standard deviation ranging from 3.3 to 6.2 mGal and a mean value ranging from -0.7 mGal to -1.9 mGal.