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arXiv · 0712.0607

Test of the Equivalence Principle Using a Rotating Torsion Balance

S. Schlamminger·K. -Y. Choi·T. A. Wagner·J. H. Gundlach·E. G. Adelberger
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Abstract

We used a continuously rotating torsion balance instrument to measure the acceleration difference of beryllium and titanium test bodies towards sources at a variety of distances. Our result Delta a=(0.6+/-3.1)x10^-15 m/s^2 improves limits on equivalence-principle violations with ranges from 1 m to infinity by an order of magnitude. The Eoetvoes parameter is eta=(0.3+/-1.8)x10^-13. By analyzing our data for accelerations towards the center of the Milky Way we find equal attractions of Be and Ti towards galactic dark matter, yielding eta=(-4 +/- 7)x10^-5. Space-fixed differential accelerations in any direction are limited to less than 8.8x10^-15 m/s^2 with 95% confidence.

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S. Schlamminger, K. -Y. Choi, T. A. Wagner, J. H. Gundlach, E. G. Adelberger. 2007-12-04. Test of the Equivalence Principle Using a Rotating Torsion Balance. https://doi.org/10.1103/physrevlett.100.041101

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