Absolute measurement of thermal noise in a resonant shortrange force experiment
Abstract
Planar, doubletorsional oscillators are especially suitable for shortrange macroscopic force search experiments, since they can be operated at the limit of instrumental thermal noise. As a study of this limit, we report a measurement of the noise kinetic energy of a polycrystalline tungsten oscillator in thermal equilibrium at room temperature. The fluctuations of the oscillator in a highQ torsional mode with a resonance frequency near 1 kHz are detected with capacitive transducers coupled to a sensitive differential amplifier. The electronic processing is calibrated by means of a known electrostatic force and input from a finiteelement model. The measured average kinetic energy, E_{exp} = (2.0 ± 0.3) × 10^{21} J, is in agreement with the expected value of 1/2{{k}_{B}}T.
 Publication:

Classical and Quantum Gravity
 Pub Date:
 October 2014
 DOI:
 10.1088/02649381/31/20/205007
 arXiv:
 arXiv:1402.0145
 Bibcode:
 2014CQGra..31t5007Y
 Keywords:

 Condensed Matter  Statistical Mechanics;
 General Relativity and Quantum Cosmology;
 High Energy Physics  Phenomenology;
 Physics  Instrumentation and Detectors
 EPrint:
 28 pages, 10 figures, new title, additional references and discussion of force sensitivity, minor corrections