title: A simple pendulum laser interferometer for determining the gravitational constant.
abstract: We present a detailed account of our 2004 experiment to measure the Newtonian constant of gravitation with a suspended laser interferometer. The apparatus consists of two simple pendulums hanging from a common support. Each pendulum has a length of 72 cm and their separation is 34 cm. A mirror is embedded in each pendulum bob, which then in combination form a Fabry-Perot cavity. A laser locked to the cavity measures the change in pendulum separation as the gravitational field is modulated due to the displacement of four 120 kg tungsten masses.
authors.affiliation: JILA, University of Colorado and National Institute of Standards and Technology, Boulder, CO 80309, USA Sandia National Laboratories, Albuquerque, NM 87185, USA harold.parks@nrc-cnrc.gc.ca.
authors.forename: Harold V
authors.initials: HV
authors.lastname: Parks
authors.affiliation: JILA, University of Colorado and National Institute of Standards and Technology, Boulder, CO 80309, USA Institute for Gravitational Research, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, UK.
authors.forename: James E
authors.initials: JE
authors.lastname: Faller
keywords: Fabry–Perot interfometer; gravitational constant; physical constants; precision measurement