Cover Story(Vol.17, Iss.1):Participation in the absolute gravity comparison with a compact cold atom gravimeter
At: 2019/1/22 11:20:19 by admin

High-precision measurementof absolute gravity is very important in Geophysics, Geodesy, Hydrology, Seismology,etc. It is difficult to evaluate the accuracy of an absolute gravimeter (AG) byitself, since the local absolute gravity value is always changing with time andposition. Therefore, the comparison between different high-precision absolutegravimeters is of great importance for the evaluation of the instrumentaccuracy.

Researchers from Zhejiang University ofTechnology and Zhejiang University reported their compact cold atom gravimeter(CCAG) for participating in the first Asia-Pacific Comparison of AbsoluteGravimeters (APMP.M.G-K1), which was the first CCAG participating in a RegionalAbsolute Gravity Comparison in China. Theprinciple of the CCAG is based on the matter wave interference. The test massin the CCAG is the microcosmic atoms rather than the classic object, whichmakes the CCAG more suitable for the continuous gravity monitoring.  The accuracy of this gravimeter was evaluated to be about 19 μGal after thecorrection of the main systematic errors. The sensitivity was estimated to be90  without any vibration isolation system during measurement. Thiswork has been published in Chinese Optics Letters, Volume 17, Issue 1, 2019 (ZhijieFu, et al., Participationin the absolute gravity comparison with a compact cold atom gravimeter).

Professor Qiang Lin, director of the group,believes that there are still spaces to improve the absolute accuracy of theCCAG. The successful participation and measurement of the CCAG in the APMP.M.G-K1 provides valuable experiences for the improvement ofthis kind of gravimeter.

Basedon the comparison results, further work will be focused on the improvement ofaccuracy and the suppression of systematic noises.

Graphics Description:A compact cold atom gravimeter participating inthe Comparison of Absolute Gravimeters.

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