The NAOMI GAZL multispecies differential absorption lidar: realization and testing on the TADI gas leak simulation facility

International audienceWe report on a differential absorption lidar, designed for remote detection of CH 4 and CO 2 , based on a single-frequency 1.57-1.65 µm parametric oscillator/amplifier system. The lidar is tested on a controlled gas release facility

MICROSCOPE mission analysis, requirements and expected performance

The MICROSCOPE mission aimed to test the Weak Equivalence Principle (WEP) to a precision of $10^{-15}$. The WEP states that two bodies fall at the same rate on a gravitational field independently of their mass or composition. In MICROSCOPE, two masses of different compositions (titanium and platinum alloys) are placed on a quasi-circular trajectory around the Earth. They are the test-masses of a double accelerometer. The measurement of their accelerations is used to extract a potential WEP violation that would occur at a frequency defined by the motion and attitude of the satellite around the Earth. This paper details the major drivers of the mission leading to the specification of the major subsystems (satellite, ground segment, instrument, orbit...). Building upon the measurement equation, we derive the objective of the test in statistical and systematic error allocation and provide the mission's expected error budget.Comment: References update

MICROSCOPE mission: first results of a space test of the equivalence principle

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 δ(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

Development of High Precision Test Masses for the MICROSCOPE Space Project

International audienceThe MICROSCOPE (MicroSatellite à traînée Compensée pour l'Observation du Principe d'Equivalence) project is an orbit-based mission to verify the Weak Equivalent Principle with an uncertainty of 10-15. To achieve this goal two differential accelerometer, each equipped with two high precision test masses (made of PtRh10 and TiAl6V4 in the form of hollow cylinders with four flats at the outer shell and six precision countersinks at each face), are to be launched in Spring 2016 and shall orbit the earth for approx. one and a half year

First Steps of Maturation Towards Space of Nested Cavity Optical Parametric Oscillator and Amplifiers for DIAL Based on Periodically Poled Nonlinear Materials

We report on the first steps of maturation towards space of a nested cavity optical parametric oscillator and amplifiers, based on periodically poled nonlinear materials, emitting in the 2µm range for multi species differential absorption lidar (DIAL)

First Steps of Maturation Towards Space of Nested Cavity Optical Parametric Oscillator and Amplifiers for DIAL Based on Periodically Poled Nonlinear Materials

We report on the first steps of maturation towards space of a nested cavity optical parametric oscillator and amplifiers, based on periodically poled nonlinear materials, emitting in the 2µm range for multi species differential absorption lidar (DIAL)

NAOMI GAZL: A Multispecies DIAL Tested on the TADI Gas Leak Simulation Facility

We report on a direct detection differential absorption lidar (DIAL), designed for remote detection of CH4 and CO2. The system is based on a single-frequency optical parametric oscillator/amplifier system, tunable in the 1.57-1.65 µm range. The DIAL system, called NAOMI GAZL, was tested on a controlled gas release facility in October 2018

NAOMI GAZL: A Multispecies DIAL Tested on the TADI Gas Leak Simulation Facility

We report on a direct detection differential absorption lidar (DIAL), designed for remote detection of CH4 and CO2. The system is based on a single-frequency optical parametric oscillator/amplifier system, tunable in the 1.57-1.65 µm range. The DIAL system, called NAOMI GAZL, was tested on a controlled gas release facility in October 2018

Microscope instrument in-flight characterization

International audienceSince 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 consolidate the scientific measurements and the subsequent conclusions drawn from them. Over the course of the mission we validated the servo-control and even updated the PID control laws for each inertial sensor. Thanks to several dedicated experiments and the analysis of the instrument sensitivities, we have been able to identify a number of instrument characteristics such as biases, gold wire and electrostatic stiffnesses, non linearities, couplings and free motion ranges of the test-masses, which may first impact the scientific objective and secondly the analysis of the instrument good operation