LISA Pathfinder: Understanding DWS noise performance for the LISA mission

11th International LISA Symposium

Wissel, Lennart^1

Max Planck Institute for Gravitational Physics, Albert Einstein Institute, Callinstraβe 38, Hannover

30167, Germany^1

关键词: Differential displacements;    Differential interferometers;    Differential wavefront sensing;    Laser interferometer space antenna;    LISA Pathfinder;    Noise performance;    Out-of-plane angles;    Point-ahead angle;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/840/1/012044/pdf
DOI  :  10.1088/1742-6596/840/1/012044

来源: IOP

【 摘 要 】

ESA's L3 Laser Interferometer Space Antenna (LISA) mission contains a mechanism to compensate for out-of-plane angles between the received and emitted beams of the three satellites. Depending on the configuration of this Point-Ahead Angle Mechanism (PAAM) it is expected to contribute readout noise through Differential Wavefront Sensing (DWS). This was investigated with LISA Pathfinder (LPF) through a dedicated investigation. One of the two free-falling test masses was rotated via the on-board electrostatic actuators while the resulting angular noise in the differential interferometer between the two test masses was measured. For angles between -250 μrad to 250 μrad and corresponding contrast in the range of 59.4 % to 97.9 % an increased spectral density was found. The differential displacement noise remains almost unchanged for these misalignments.