INVESTIGATION IN THE LOCAL GRAVITY FIELD OF A FORCE LABORATORY OF PTB
Abstract
It belongs to the functions of the National Institutes of Metrology to realise a force scale of highest accuracy. The uncertainty of the resulting force basically depends on the precise knowledge of local gravity acceleration. This paper describes the spatial determination of the local gravity field in the force laboratory of the PTB on the basis of a new highly precise gravity network. A special emphasis is placed on the influence due to gravity of the surrounding masses placed in the laboratory on the single gravity value. It can be shown that the installation of the new 2 MN deadweight force standard machine has led to a significant change in the local gravity field. Temporal variations caused by earth tides are proved by long-term registrations and are considered in a correction term for the gravity value. The periodical change of gravity reaches a level of 10<sup>-7</sup> <i>g</i> in the equator region and at present does not affect the uncertainty budget of the force measurement.
Event details
- Event
- Joint International Conference on Force, Mass, Torque, Hardness and Civil Engineering Metrology in the age of globalization
- Technical Committee
- TC3
- Place
- Celle, GERMANY
- Time
- 24 September 2002 - 26 September 2002