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Vladislav Gerginov with NIST F4
    
  Appears In
      
      Second: The PresentThe Twelve Days of Metric
      
            Vladislav Gerginov makes final adjustments on the new microwave cavity, the “heart” of NIST’s new fountain clock NIST F4. This copper cavity is where microwaves interact with the cesium atoms, causing them to change state and defining the second. Once completed, scientists hope to use NIST F4 as the new reference standard for the second.

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                                R. Jacobson/NIST HEADQUARTERS
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