Effect of solar free oscillations on TianQin's range acceleration noise

TL;DR

This paper assesses the impact of solar free oscillations on TianQin's range acceleration noise, finding that their effect is negligible compared to mission noise requirements.

Contribution

It provides a detailed analysis of solar free oscillation-induced noise on TianQin using high-precision orbit modeling and gravity-field data.

Findings

Solar free oscillation noise is two orders of magnitude below noise requirement.

The effect of solar oscillations on TianQin's measurements is negligible.

The study enhances understanding of orbital noise sources for space-based gravitational wave detectors.

Abstract

TianQin is a proposed space-based gravitational-wave detector mission to be deployed and operated in high Earth orbits. As a sequel to [Zhang et al. Phys. Rev. D 103, 062001 (2021)], we investigate a type of ``orbital noise'' in TianQin's range acceleration that is caused by gravitational perturbation associated with solar free oscillations. Frequencies of such oscillations are typically within TianQin's measurement band of 0.1 mHz--1 Hz, and the disturbance level needs careful assessment. By using high-precision orbit propagation and adding the Sun's time-variable oblateness $J_2$ to detailed gravity-field models, we examine the effect in the frequency domain and show that the solar free oscillation noise is expected to be two orders of magnitude lower than the noise requirement on single links and hence has little impact on the mission.