Pierre Touboul, Gilles Métris, Manuel Rodrigues, Yves André, Quentin Baghi, Joël Bergé, Damien Boulanger, Stefanie Bremer, Patrice Carle, Ratana Chhun, Bruno Christophe, Valerio Cipolla, Thibault Damour, Pascale Danto, Hansjoerg Dittus, Pierre Fayet, Bernard Foulon, Claude Gageant, Pierre-Yves Guidotti, Daniel Hagedorn, Emilie Hardy, Phuong-Anh Huynh, Henri Inchauspe, Patrick Kayser, Stéphanie Lala, Claus Lämmerzahl, Vincent Lebat, Pierre Leseur, Françoise Liorzou, Meike List, Frank Löffler, Isabelle Panet, Benjamin Pouilloux, Pascal Prieur, Alexandre Rebray, Serge Reynaud, Benny Rievers, Alain Robert, Hanns Selig, Laura Serron, Timothy Sumner, Nicolas Tanguy and Pieter Visser.
Physical Review Letters (2017) 119, 231101.
https://doi.org/10.1103/PhysRevLett.119.231101
According to the weak equivalence principle, all bodies should fall at the same rate in a gravitational field. The MICROSCOPE satellite, launched in April 2016, aims to test its validity at the 10−15 precision level, by measuring the force required to maintain two test masses (of titanium and platinum alloys) exactly in the same orbit. A nonvanishing result would correspond to a violation of the equivalence principle, or to the discovery of a new long-range force. Analysis of the first data gives d(Ti, Pt) = [-1 ± 9(stat) ± 9(syst)] × 10−15 (1σ statistical uncertainty) for the titanium-platinum Eötvös parameter characterizing the relative difference in their free-fall accelerations.
