TOUBOUL , Pierre

MICROSCOPE is a space mission launched in 2016 that aims to test the validity of the Equivalence Principle (EP), the main postulate of General Relativity (GR), with a precision never reached before (Touboul et al. (2001)). EP states that two bodies of different compositions and masses fall with the same acceleration in the same gravitational...

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The MICROSCOPE space experiment aimed to test the Equivalence Principle with a much better accuracy than ever before. Its principle is to compare the free fall of concentric test masses embedded in a space accelerometer onboard a satellite orbiting the Earth. The effect of non-gravitational forces on the motion of the satellite is strongly...

The MICROSCOPE space mission aims at testing the Equivalence Principle with an accuracy of 10e-15. To be launched on April 2016, the CNES microsatellite embarks the instrument that should test for the first time in space the foundation of General Relativity. The expected results whether they confirm or not the Equivalence Principle will bring a...

The MICROSCOPE space mission, launched on April 25, 2016, aims to test the weak equivalence principle (WEP) with a 10^−15 precision. Reaching this performance requires an accurate and robust data analysis method, especially since the possible WEP violation signal will be dominated by a strongly colored noise. An important complication is...

The MICROSCOPE space mission aims at testing the Equivalence Principle (EP) with an accuracy of 10-15. The instrument will be embarked on board a drag-free microsatellite orbiting the Earth, and consists in a differential electrostatic accelerometer composed of two cylindrical test masses submitted to the same gravitational field but made of...

Several space tests of gravity laws have already been performed but the MICROSCOPE mission is the first one to be fully dedicated to the test of the Equivalence Principle. The dedicated payload is now under qualification and the rather large micro satellite will be produced by Cnes for a launch at beginning of 2015. Each of the two differential...

MICROSCOPE is a fundamental physics space mission which aims at testing the Equivalence Principle (EP) with an accuracy of 10-15. The gravitational signal is measured precisely by a differential electrostatic accelerometer which includes two cylindrical test masses made of different materials. The accelerometer is on-board a drag-free...

The aim of the MICROSCOPE space mission is to test the weak equivalence principle (WEP) with a precision of 10−15, 100 times better than on-ground experiments. The WEP violation signal that we look for in flight has a particular frequency signature and must be extracted from the measurement of accelerations dominated by a colored noise...

The analysis of physical measurements often copes with highly correlated noises and interruptions caused by outliers, saturation events, or transmission losses. We assess the impact of missing data on the performance of linear regression analysis involving the fit of modeled or measured time series. We show that data gaps can significantly...

The MICROSCOPE space mission aims at testing the Equivalence Principle (EP) with an accuracy of 10-15. The test is based on the precise measurement delivered by a differential electrostatic accelerometer onboard a drag-free satellite which includes two cylindrical test masses submitted to the same gravitational field and made of different...

The space mission MICROSCOPE aims at testing the Equivalence Principle (EP) with an accuracy of 10-15. The test is based on the precise measurement delivered by a differential electrostatic accelerometer onboard a drag-free microsatellite which includes two cylindrical test masses submitted to the same gravitational field and made of different...

The existence of a light or massive scalar field with a coupling to matter weaker than gravitational strength is a possible source of violation of the weak equivalence principle. We use the first results on the Eötvös parameter by the MICROSCOPE experiment to set new constraints on such scalar fields. For a massive scalar field of mass smaller...

The existence of a light or massive scalar field with a coupling to matter weaker than gravitational strength is a possible source of violation of the weak equivalence principle. We use the first results on the Eötvös parameter by the MICROSCOPE experiment to set new constraints on such scalar fields. For a massive scalar field of mass smaller...

This paper introduces the current special issue focussed on the MICROSCOPE mission. This mission is the first experimental test in space of the weak equivalence principle (WEP) using man-made test-masses—as opposed to astronomical tests—with the goal to reach a precision two orders of magnitude better than ground-based experiments. Selected in...

Launched in April 2016, the satellite of the MICROSCOPE space mission should end its operations in autumn 2018. The science objective is the test of the weak Equivalence Principle (EP) with an accuracy of 10-15. The EP is one cornerstone of General Relativity (GR); it states the equivalence between gravitational and inertial mass. Most of the...

This article is dedicated to the use the MICROSCOPE mission's data to test chameleon theory of gravity. We take advantage of the technical sessions aimed to characterize the electrostatic stiffness of MICROSCOPE's instrument intrinsic to its capacitive measurement system. Any discrepancy between the expected and measured stiffness may result...

This article is dedicated to the use the MICROSCOPE mission's data to test chameleon theory of gravity. We take advantage of the technical sessions aimed to characterize the electrostatic stiffness of MICROSCOPE's instrument intrinsic to its capacitive measurement system. Any discrepancy between the expected and measured stiffness may result...

Since the years 2000, three space missions, CHAMP, GRACE, and GOCE, have led us to consider the Earth's gravitational field and its measurement in a new light, using dedicated sensors and adequate data processing, revealing the changes in the Earth's field as the true signal rather than the disturbing terms in addition to the geostatic...

Testing the weak equivalence principle to a precision of 10$^{−15}$ requires a quantity of data that give enough confidence on the final result: ideally, the longer the measurement the better the rejection of the statistical noise. The science sessions had a duration of 120 orbits maximum and were regularly repeated and spaced out to...

The MICROSCOPE experiment was designed to test the weak equivalence principle in space, by comparing the low-frequency dynamics of cylindrical 'free-falling' test masses controlled by electrostatic forces. We use data taken during technical sessions aimed at estimating the electrostatic stiffness of MICROSCOPE's sensors to constrain a...

MICROSCOPE's space test of the weak equivalence principle (WEP) is based on the minute measurement of the difference of accelerations experienced by two test masses as they orbit the Earth. A detection of a violation of the WEP would appear at a well-known frequency f$_{EP}$ depending on the satellite's orbital and spinning frequencies....

After performing highly sensitive acceleration measurements during two years of drag-free flight around the Earth, MICROSCOPE provided the best constraint on the weak equivalence principle (WEP) to date. Beside being a technological challenge, this experiment required a specialised data analysis pipeline to look for a potential small signal...

Since the MICROSCOPE instrument aims to measure accelerations as low as a few 10$^{−15}$ m s$^{−2}$ and cannot operate on ground, it was necessary to have a large time dedicated to its characterization in flight. After its release and first operation, the characterization experiments covered all the aspects of the instrument design in order to...