Current error estimates for LISA spurious accelerations

Abstract

The performance of the LISA gravitational wave detector depends critically on limiting spurious accelerations of the fiducial masses. Consequently, the requirements on allowable acceleration levels must be carefully allocated based on estimates of the achievable limits on spurious accelerations from all disturbances. Changes in the allocation of requirements are being considered, and are proposed here. The total spurious acceleration error requirement would remain unchanged, but a few new error sources would be added, and the allocations for some specific error sources would be changed. In support of the recommended revisions in the requirements budget, estimates of plausible acceleration levels for 17 of the main error sources are discussed. In most cases, the formula for calculating the size of the effect is known, but there may be questions about the values of various parameters to use in the estimates. Different possible parameter values have been discussed, and a representative set is presented. Improvements in our knowledge of the various experimental parameters will come from planned experimental and modelling studies, supported by further theoretical work.

Interaction between Stray Electrostatic Fields and a Charged Free-Falling Test Mass

“…The mutual interaction between charge and stray potentials [22][23][24][25] can be written, to linear order in q,…”

Gravitational disturbances in drag-free spacecraft

“…Thermal-gravitational effects contribute as a fluctuating force noise [8] and they are likely to shift the local gravitational field value. There could also be some distortions due to, for example, tidal effects [9].…”

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