中国物理B ›› 1998, Vol. 7 ›› Issue (2): 81-88.doi: 10.1088/1004-423X/7/2/001

• GENERAL •    下一篇

OPTIMUM DURATION OF MEASUREMENT FOR REDUCING THERMAL NOISE LIMITATIONS IN TORSION PENDULUM EXPERIMENTS

胡忠坤, 罗俊   

  1. Department of Physics, Huazhong University of Science and Technology, Wuhan 430074,China
  • 收稿日期:1997-06-09 出版日期:1998-02-20 发布日期:1998-02-20
  • 基金资助:
    Project supported by the National Natural Science Foundation of China and the Fok Ying-tung Educational Foundation.

OPTIMUM DURATION OF MEASUREMENT FOR REDUCING THERMAL NOISE LIMITATIONS IN TORSION PENDULUM EXPERIMENTS

HU ZHONG-KUN (胡忠坤), LUO JUN (罗俊)   

  1. Department of Physics, Huazhong University of Science and Technology, Wuhan 430074,China
  • Received:1997-06-09 Online:1998-02-20 Published:1998-02-20
  • Supported by:
    Project supported by the National Natural Science Foundation of China and the Fok Ying-tung Educational Foundation.

摘要: Statistical estimates of thermal noise fluctuation of a linear harmonic oscillator used to detect weak forces are reexamined with special reference to gravitational experiments. Thermal noise limitation on the measurement of displacement of an oscillator is studied. It is found that the signal response of an oscillator reaches the maximum value while the thermal noise response reaches the minimum value at the same time during the transient state of the oscillator, and the precision of the experiments in the transient state could increase about two orders higher than that in the equilibrium state for typical experiments. It is also found that there is an optimum duration of measurement in which the uncertainty due to thermal noise in this period is the least.

Abstract: Statistical estimates of thermal noise fluctuation of a linear harmonic oscillator used to detect weak forces are reexamined with special reference to gravitational experiments. Thermal noise limitation on the measurement of displacement of an oscillator is studied. It is found that the signal response of an oscillator reaches the maximum value while the thermal noise response reaches the minimum value at the same time during the transient state of the oscillator, and the precision of the experiments in the transient state could increase about two orders higher than that in the equilibrium state for typical experiments. It is also found that there is an optimum duration of measurement in which the uncertainty due to thermal noise in this period is the least.

中图分类号:  (Noise)

  • 05.40.Ca
45.05.+x (General theory of classical mechanics of discrete systems)