Luo Jie, Wu Wei-Huang, Xue Chao, Shao Cheng-Gang, Zhan Wen-Ze, Wu Jun-Fei, Milyukov Vadim
School of Mechanical Engineering and Electronic Information, China University of Geosciences, Wuhan 430074, People's Republic of China.
MOE Key Laboratory of Fundamental Physical Quantities Measurement, School of Physics, Huazhong University of Science and Technology, Wuhan 430074, People's Republic of China.
Rev Sci Instrum. 2016 Aug;87(8):084501. doi: 10.1063/1.4960398.
In the measurement of the gravitational constant G with angular acceleration method, the equilibrium position of torsion pendulum with tungsten fiber undergoes a linear slow drift, which results in a quadratic slow drift on the angular velocity of the torsion balance turntable under feedback control unit. The accurate amplitude determination of the useful angular acceleration signal with known frequency is biased by the linear slow drift and the coupling effect of the drifting equilibrium position and the room fixed gravitational background signal. We calculate the influences of the linear slow drift and the complex coupling effect on the value of G, respectively. The result shows that the bias of the linear slow drift on G is 7 ppm, and the influence of the coupling effect is less than 1 ppm.
在用角加速度法测量引力常数G时，采用钨丝的扭秤平衡位置会发生线性缓慢漂移，这会在反馈控制单元作用下使扭秤转盘的角速度产生二次缓慢漂移。已知频率的有用角加速度信号的精确幅度测定会受到线性缓慢漂移以及漂移平衡位置与室内固定引力背景信号的耦合效应的影响。我们分别计算了线性缓慢漂移和复杂耦合效应对G值的影响。结果表明，线性缓慢漂移对G的偏差为7 ppm，耦合效应的影响小于1 ppm。
