Search Publications
MICROSCOPE: systematic errors
Bergé, Joel; Chhun, Ratana; Métris, Gilles +19 more
The MICROSCOPE mission aims to test the weak equivalence principle (WEP) in orbit with an unprecedented precision of 10-15 on the Eötvös 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 b…
MICROSCOPE mission scenario, ground segment and data processing
Bergé, Joel; Chhun, Ratana; Métris, Gilles +9 more
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 accommo…
MICROSCOPE mission: statistics and impact of glitches on the test of the weak equivalence principle
Bergé, Joel; Métris, Gilles; Rodrigues, Manuel +6 more
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. Con…
The MICROSCOPE space mission: the first test of the equivalence principle in a space laboratory
Bergé, Joel; Chhun, Ratana; Métris, Gilles +4 more
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 199…
In the realm of the Hubble tension-a review of solutions
Riess, Adam G.; Di Valentino, Eleonora; Melchiorri, Alessandro +6 more
The simplest ΛCDM model provides a good fit to a large span of cosmological data but harbors large areas of phenomenology and ignorance. With the improvement of the number and the accuracy of observations, discrepancies among key cosmological parameters of the model have emerged. The most statistically significant tension is the 4σ to 6σ disagreem…
The BepiColombo solar conjunction experiments revisited
Cappuccio, Paolo; di Stefano, Ivan; Iess, Luciano
BepiColombo ESA/JAXA mission is currently in its 7 year cruise phase towards Mercury. The Mercury orbiter radioscience experiment (MORE), one of the 16 experiments of the mission, will start its scientific investigation during the superior solar conjunction (SSC) in March 2021 with a test of general relativity (GR). Other solar conjunctions will f…
Low-energy electromagnetic processes affecting free-falling test-mass charging for LISA and future space interferometers
Grimani, Catia; Villani, Mattia; Fabi, Michele +1 more
Galactic cosmic rays and solar energetic particles charge gold-platinum, free-falling test masses (TMs) on board interferometers for the detection of gravitational waves in space. The charging process induces spurious forces on the test masses that affect the sensitivity of these instruments mainly below 10-3 Hz. Geant4 and FLUKA Monte …
Comparison of light-time formulations in the post-Newtonian framework for the BepiColombo MORE experiment
Cappuccio, Paolo; di Stefano, Ivan; Cascioli, Gael +1 more
The ESA/JAXA BepiColombo mission, launched on 20 October 2018, is currently in cruise toward Mercury. The Mercury Orbiter Radio-science Experiment (MORE), one of the 16 experiments of the mission, will exploit range and range-rate measurements collected during superior solar conjunctions to better constrain the post-Newtonian parameter γ. The MORE…
Charge induced acceleration noise in the LISA gravitational reference sensor
Sumner, Timothy J.; Wass, Peter J.; Conklin, John W. +2 more
The presence of free charge on isolated proof-masses, such as those within space-borne gravitational reference sensors, causes a number of spurious forces which will give rise to associated acceleration noise. A complete discusssion of each charge induced force and its linear acceleration noise is presented. The resulting charge acceleration noise…
Modeling spurious forces on the LISA spacecraft across a full solar cycle
Frank, Barrett M.; Piotrzkowski, Brandon; Bolen, Brett +2 more
One source of noise for the laser interferometer space antenna (LISA) will be time-varying changes of the space environment in the form of solar wind particles and photon pressure from fluctuating solar irradiance. The approximate magnitude of these effects can be estimated from the average properties of the solar wind and the solar irradiance. We…