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2015 Gold Medal Award

AWARD CITATION

This duo is recognized for designing, constructing, operating, and continually improving the world’s most accurate official time and frequency standard (atomic clock), the NIST-F2 laser-cooled cesium-fountain primary frequency standard. NIST-F2 is the U.S. national standard for the second, is one of the most visible and widely used assets of the Department of Commerce, substantially outperforms past atomic clocks, and is demonstrably the most accurate primary standard in the world.

GROUP AWARD

Steven Jefferts

Physicist
Laboratory Programs, Physical Measurement Laboratory, Time and Frequency Division

Thomas Heavner

Physicist
Laboratory Programs, Physical Measurement Laboratory, Time and Frequency Division