Comparison of the INRIM and PTB lattice-spacing standards
نویسنده
چکیده
To base the kilogram definition on the atomic mass of the Si atom, the present relative uncertainty of the Si lattice parameter must lowered to 3 × 10. To achieve this goal, a new experimental apparatus capable of a centimetre measurement-baseline has been made at the INRIM. The comparison between the determinations of the lattice parameter of crystals MO*4 of INRIM and WASO 4.2a of PTB is intended to verify the measurement capabilities and to assess the limits of this experiment. Submitted to: Metrologia PACS numbers: 06.20.-f, 06.20.Jr, 61.05.C-
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تاریخ انتشار 2009