Determination of the Avogadro constant by counting the atoms in a 28Si crystal.

  title={Determination of the Avogadro constant by counting the atoms in a 28Si crystal.},
  author={Birk Andreas and Yasushi Azuma and Guido Bartl and Peter Becker and Horst Bettin and Michael Borys and Ingo Busch and Malcolm Gray and Paul Fuchs and Kenichi Fujii and Hiroyuki Fujimoto and Ernest G. Kessler and Michael Krumrey and Ulrich Kuetgens and Naoki Kuramoto and Giovanni Mana and Peter Manson and Enrico Massa and Shigeki Mizushima and Arnold Nicolaus and Alain Picard and Axel Pramann and Olaf Rienitz and Detlef Schiel and Staf Valkiers and Atsushi Waseda},
  journal={Physical review letters},
  volume={106 3},
The Avogadro constant links the atomic and the macroscopic properties of matter. Since the molar Planck constant is well known via the measurement of the Rydberg constant, it is also closely related to the Planck constant. In addition, its accurate determination is of paramount importance for a definition of the kilogram in terms of a fundamental constant. We describe a new approach for its determination by counting the atoms in 1 kg single-crystal spheres, which are highly enriched with the… 

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