Effect of Earth-Moon's gravity on TianQin's range acceleration noise

Abstract

TianQin is a proposed space gravitational-wave detection mission using circular high Earth orbits. The geocentric concept has raised questions about the disturbing effect of the nearby gravity field of the Earth-Moon system on the highly-sensitive intersatellite ranging measurements. Here we examine the issue through high precision numerical orbit simulation with detailed gravity-field models. By evaluating range accelerations between distant free-falling test masses, the study shows that the majority of the Earth-Moon's gravity disturbances are not in TianQin's detection frequency band above 10 −4 Hz, and hence present no showstoppers to the mission.

Orbital effects on time delay interferometry for TianQin

“…Analytic approximation of the orbit coordinates for each satellite and the strain output of a Michelson interferometer for arbitrary incoming GWs are studied in [19]. A series of study on TianQin's orbit and constellation, including constellation stability optimization [20], orbital orientation and radius selection [21], eclipse avoidance [22], and the Earth-Moon's gravity disturbance evaluation [23], have been conducted. The recent progresses in the investigations of both science case and technological realization for TianQin can be found in [24][25][26][27][28][29][30][31][32][33][34].…”