SI frequency reference for the second
The unperturbed ground-state hyperfine transition of caesium-133; the defining value is exact, while realizations have uncertainty.
Based on the final manuscript · Preface; Chapter 1
The unperturbed ground-state hyperfine transition of caesium-133; the defining value is exact, while realizations have uncertainty.
Chapter reference: Final consolidated manuscript · Chapter 1, §I, metrological background; BIPM second definition (external definition) · ASD-BOOK-ddbade997b45
Source and ID
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Return to premises and derivationAdopted source, conditions and previous versions
Final consolidated manuscript · Chapter 1, §I, metrological background; BIPM second definition (external definition)
The unperturbed ground-state hyperfine transition of caesium-133; the defining value is exact, while realizations have uncertainty.
Conditions retained in this adoption
- Same measurand, reference conditions and propagation/counting basis
- LVE additionally uses moving configurations and path pairing
Specific unresolved source issues
- FINAL-CH1-QUANTITY
- FINAL-CH1-KRYPTON
Source locators: p0300 · p0559
Manuscript SHA-256: ddbade997b45913248e588953b1d27ccb9c7c206c3c8d992d3aef2364a64836e
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Previous source, retained as history
FND-3dde8d8e081d · BIPM 秒定义；序章计量背景
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