ASTROD, ASTROD I and their gravitational-wave sensitivities

TL;DR

ASTROD and ASTROD I are space missions designed to test relativistic gravity, measure solar system parameters, and detect gravitational waves, with sensitivities compared to LISA and radio Doppler tracking.

Contribution

This paper details the payload and accelerometer requirements for ASTROD I and analyzes their gravitational-wave sensitivities relative to other detection methods.

Findings

ASTROD I's gravitational-wave sensitivity is characterized and compared to LISA.

ASTROD's sensitivity surpasses that of traditional radio Doppler tracking.

The paper establishes the feasibility of using ASTROD for gravitational-wave detection.

Abstract

ASTROD (Astrodynamical Space Test of Relativity using Optical Devices) is a mission concept with three spacecraft -- one near L1/L2 point, one with an inner solar orbit and one with an outer solar orbit, ranging coherently with one another using lasers to test relativistic gravity, to measure the solar system and to detect gravitational waves. ASTROD I with one spacecraft ranging optically with ground stations is the first step toward the ASTROD mission. In this paper, we present the ASTROD I payload and accelerometer requirements, discuss the gravitational-wave sensitivities for ASTROD and ASTROD I, and compare them with LISA and radio-wave PDoppler-tracking of spacecraft.