TITLE

Source mass and positioning system for an accurate measurement of G

AUTHOR(S)
Lamporesi, G.; Bertoldi, A.; Cecchetti, A.; Duhlach, B.; Fattori, M.; Malengo, A.; Pettorruso, S.; Prevedelli, M.; Tino, G. M.
PUB. DATE
July 2007
SOURCE
Review of Scientific Instruments;Jul2007, Vol. 78 Issue 7, p075109
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
We report on a system of well-characterized source masses and their precision positioning system for a measurement of the Newtonian gravitational constant G using atoms as probes. The masses are 24 cylinders of 50 mm nominal radius, 150.2 mm nominal height, and mass of about 21.5 kg, sintered starting from a mixture of 95.3% W, 3.2% Ni, and 1.5% Cu. Density homogeneity and cylindrical geometry have been carefully investigated. The positioning system independently moves two groups of 12 cylinders along the vertical direction by tens of centimeters with a reproducibility of a few microns. The whole system is compatible with a resolution ΔG/G<10-4.
ACCESSION #
26222290

 

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