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New Results From Previously Reported NBS Fundamental Constant Determinations
1National Bureau of Standards, Gaithersburg, MD 20899.
Journal of Research of the National Bureau of Standards (1977)
|September 27, 2021
Summary
New analysis of electric-unit experiments provides accurate SI values for fundamental constants. This includes the fine-structure constant (α), Avogadro constant (NA), and quantized Hall resistance (RH).
Area of Science:
- Metrology and fundamental physics.
- Electrical metrology and quantum phenomena.
Background:
- Accurate determination of fundamental constants is crucial for scientific advancement.
- Previous experiments have established methods for measuring electric-unit-dependent quantities.
Purpose of the Study:
- To derive accurate, indirect SI values for key fundamental constants.
- To re-evaluate previously reported experimental results using a new treatment.
Main Methods:
- Analysis of data from three electric-unit-dependent fundamental constant experiments.
- Application of a new treatment to previously reported experimental results.
Main Results:
- Accurate, indirect SI values were obtained for several fundamental constants.
- Key determined quantities include the fine-structure constant (α), Avogadro constant (NA), Josephson frequency-voltage ratio (2e/h), and quantized Hall resistance (RH).
Conclusions:
- The new treatment of experimental data yields reliable indirect SI values for fundamental constants.
- This work contributes to the precise definition and understanding of SI units and physical constants.
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