THE SCHEME FOR DESIGNING THE LASER INTERFEROMETER GRAVITY GRADIOMETER
WU Qiong1, TENG Yun-tian1, GUO You-guang2
1. Institute of Geophysics, China Earthquake Administration, Beijing 100081, China;
2. Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China
Two kinds of gravity gradiometer are described in this paper: one is laser interferometer and the other is atom interferometer. The authors have found that free fall gradiometery offers much promise for dynamic measurements and the free fall system can either use macroscopic objects in free-fall (mirrors) or atomic fountains. The two systems have similar intrinsic sensitivities. Based on the initial gravity gradient measuring experiment with NIM-Ⅱ, the authors put forward two ideas to design the gravity gradiometer: Single-Interferometer and Dual-Interferometer. The authors favor the second one in that it can satisfy the precision requirement at the same size as the traditional absolute gradiometer.
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