The first phase of the TÜBİTAK UME Kibble Balance Experiment, designed to realize the new definition of the kilogram unit, was successfully completed.

TÜBİTAK UME has successfully completed the first phase of the Kibble Balance Experiment, in which it has been working to realize the new definition of the kilogram unit.

As part of the project initiated in 2014 for the realization of the new definition of the kilogram, one of the basic units of the International System of Units (SI), which is expected to be in force as of May 20, 2019, a completely new measurement concept was created by following an alternative path to the leading institutes in the field of scientific metrology, and the Turkish brand of Kibble balance experiments was developed using appropriate technologies.

Based on the principle of balancing mechanical and electrical power, Kibble balancing experimental setups can be designed with different geometries and experimental protocols. Turkey, one of the few countries in the world to have this setup, also contributes to the studies carried out worldwide with TÜBİTAK UME Oscillating Magnet Kibble Balancing Experiment setup.

At the end of the successfully completed first phase of the project 3 x 10^-7  Although the relative uncertainty level was reached recently, the uncertainty levels of institutes that have been working in this field for relatively longer years have been achieved in a short period of time.

In the second phase, in which the National Kilogram Prototype will be created, 2 x 10^-8  relative uncertainty level is aimed to be reached. If this target is achieved, the country will no longer be dependent on external sources for securing national mass measurements, and TÜBİTAK UME will be in a position to provide international mass calibration services to institutes that do not have a primary method and even provide technology transfer to developing institutes.

The current definition of the kilogram, which uses a cast, cylindrical, man-made object made of an alloy of platinum and iridium called the International Prototype Kilogram (IPK), has been used as the reference for all other kilogram measurements in the world for more than a century.

In addition to the practical difficulties of applying the current definition, the General Conference on Weights and Measures (CGPM) in 2014 decided to abandon the artifact definition and define the kilogram unit in terms of Planck's constant, which is a universal constant, since the absolute stable nature of the kilogram unit has become important in areas where precise mass measurements are needed, such as international trade, advanced technology manufacturing, human health and safety, environmental protection, global climate studies, etc.

With this new definition, which guarantees the long-term stability of the mass scale, the kilogram will be independent of time, location and person.

The Kibble (Watt) Balance Experiment is one of the two primary methods officially accepted by the Consultative Committee on Mass and Related Quantities (CCM) for the realization of the kilogram in terms of Planck's constant with the highest accuracy and lowest uncertainty, without the need to use mass standards. TÜBİTAK UME continues its efforts to become the primary method for the realization of the kilogram with the Kibble Balance setup, which it created with a completely new measurement concept.