title: A free-fall determination of the newtonian constant of gravity
abstract: Recent determinations of the Newtonian constant of gravity have produced values that differ by nearly 40 times their individual error estimates (more than 0.5%). In an attempt to help resolve this situation, an experiment that uses the gravity field of a one-half metric ton source mass to perturb the trajectory of a free-falling mass and laser interferometry to track the falling object was performed. This experiment does not suspend the test mass from a support system. It is therefore free of many systematic errors associated with supports. The measured value was G = (6.6873 +/- 0. 0094) x 10(-11) m3 kg-1 sec-2.
authors.affiliation: J. P. Schwarz and J. E. Faller, JILA, University of Colorado and National Institute of Standards and Technology, Boulder, CO 80309-0440, USA. D. S. Robertson, National Geodetic Survey, NOS, NOAA, and CIRES, University of Colorado, Bould.
authors.initials: JP
authors.lastname: Schwarz
authors.initials: DS
authors.lastname: Robertson
authors.initials: TM
authors.lastname: Niebauer
authors.initials: JE
authors.lastname: Faller