Mass determination of 1 kg silicon spheres for Avogadro project
نویسندگان
چکیده
Our work concerns the mass determination of 1 kg silicon spheres in the framework of the international Avogadro project with a view to an improved definition of the kilogram. It has been shown that the original method developed by the BIPM will attain reach the uncertainty target requested by the Avogadro group. New investigations have been initiated at the BIPM using a well adapted mass comparator and more appropriate sorption transfer masses. Preliminary measurements carried out on several 1 kg silicon spheres having a natural-oxide surface are presented.
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Mass Determination of Silicon Spheres Used for the Avogadro Project
Spheres made of a silicon single crystal with a mass of about 1 kg are used as density standards and in the context of a project for the determination of the Avogadro constant. The status of the mass determination of such silicon spheres at the PTB is presented. Special facilities and procedures used for the mass determination in air are described. Results for a single sphere and the mass diffe...
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