Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Comparison of Open and Solid Falling Retroreflector Gravimeters

Published

Author(s)

Neil Ashby, Derek Van Westrum

Abstract

We study whether the optical properties of a solid glass retroreflector influence the value of the acceleration of gravity $g$ determined by dropping both solid and open retroreflectors in an absolute ballistic gravimeter. The retroreflectors have equivalent optical centers and are dropped from the same height, at a fixed location, in the same gravimeter while recording time data corresponding to fixed fringe separation intervals of 400 fringes. The data for both types of retroreflectors are processed with commercial software, as well as with independently developed software based on a relativistic treatment of the phase difference between reference beam and test beams, and a realistic treatment of the effect of frequency modulation, with modulation index $\beta>>1$, on the interference signal. After applying corrections for polar motion, barometric admittance, tides, and ocean loading we find agreement between the values of $g$ determined with both types of retroreflectors, whether processed with commercial software or with our independently developed software. We suggest two procedures for computing relativistic corrections; the two methods agree to better than .05 $\mu$Gal.
Citation
Metrologia

Keywords

gravimeters, relativity, acceleration, retroreflectors

Citation

Ashby, N. and Van Westrum, D. (2020), Comparison of Open and Solid Falling Retroreflector Gravimeters, Metrologia, [online], https://doi.org/10.1088/1681-7575/ab7d12 (Accessed December 9, 2024)

Issues

If you have any questions about this publication or are having problems accessing it, please contact reflib@nist.gov.

Created May 29, 2020, Updated March 25, 2024