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arXiv · 2101.01243

A Low-Frequency Torsion Pendulum with Interferometric Readout

M. P. Ross·K. Venkateswara·C. A. Hagedorn·C. J. Leupold·P. W. F. Forsyth·J. D. Wegner·E. A. Shaw·J. G. Lee·J. H. Gundlach
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Abstract

We describe a torsion pendulum with a large mass-quadrupole moment and a resonant frequency of 2.8 mHz, whose angle is measured using a modified Michelson interferometer. The system achieved noise levels of $\sim200\ \text{prad}/\sqrt{\text{Hz}}$ between 0.2-30 Hz and $\sim10\ \text{prad}/\sqrt{\text{Hz}}$ above 100 Hz. Such a system can be applied to a broad range of fields from the study of rotational seismic motion and elastogravity signals to gravitational wave observation and tests of gravity.

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M. P. Ross, K. Venkateswara, C. A. Hagedorn, C. J. Leupold, P. W. F. Forsyth, J. D. Wegner, E. A. Shaw, J. G. Lee, J. H. Gundlach. 2021-04-20. A Low-Frequency Torsion Pendulum with Interferometric Readout. https://doi.org/10.1063/5.0043098

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