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arXiv · 2008.05812

Revisiting time delay interferometry for unequal-arm LISA and TAIJI

Gang Wang·Wei-Tou Ni
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Abstract

Three spacecraft of LISA/TAIJI mission follow their respective geodesic trajectories, and their interferometric arms are unequal and time-varying due to orbital dynamics. Time-delay interferometry (TDI) is proposed to suppress the laser frequency noise caused by the unequal-arm. By employing the numerical orbit, we investigate the sensitivity of the first-generation TDI configurations and their corresponding optimal A, E, and T channels. The sensitivities of T channels from Michelson and Monitor/Beacon configurations diverge from the equal-arm case in frequencies lower than 10 mHz, and their performances vary with the inequality of the arm lengths. The mismatches of the laser beam paths are evaluated in a dynamic case, and the residual laser noise in the first-generation TDI could not satisfy the mission requirement.

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Gang Wang, Wei-Tou Ni. 2022-08-02. Revisiting time delay interferometry for unequal-arm LISA and TAIJI. https://doi.org/10.1088/1402-4896%2Facd882

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