LISA Telescope: Phase noise due to pointing jitter

TL;DR

This paper investigates how pointing jitter in the LISA space-based gravitational wave detector causes phase noise, analyzing the impact of wavefront quality and telescope imperfections on signal detection accuracy.

Contribution

It provides a numerical assessment of how beam aberrations and telescope defects influence phase noise due to pointing jitter in LISA.

Findings

Pointing jitter induces measurable phase noise in LISA.

Wavefront quality significantly affects phase stability.

Telescope imperfections exacerbate jitter-induced phase fluctuations.

Abstract

In a space based gravitational wave antenna like LISA, involving long light paths linking distant emitter/receiver spacecrafts, signal detection amounts to measuring the light-distance variationsthrough a phase change at the receiver. This is why spurious phase fluctuations due to various mechanical/thermal effects must be carefully studied. We consider here a possible pointing jitter in the light beam sent from the emitter. We show how the resulting phase noise depends on the quality of the wavefront due to the incident beam impinging on the telescope and due to the imperfections of the telescope itself. Namely, we numerically assess the crossed influence of various defects (aberrations and astigmatisms), inherent to a real telescope with pointing fluctuations.