Abstract：Based on laser interference technology and free-fall theory, the National Institute of Metrology (China) has developed the latest NIM-3A type absolute gravimeter.This instrument has participated in the 9th international comparison of absolute gravimetries CCM.G-K2,according to the published result of CCM.G-K2,the NIM-3A type absolute gravimeter with the combined standard uncertainty of 5.3 μGal is agreed with the key comparison reference value and the degree of equivalence is gained.
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2017, Vol. 38 
