National Institute of Standards and Technology, Boulder Laboratories (NIST Boulder)
NIST’s Cesium Fountain Atomic Clocks
standardtime / measurement standardIndustry: Aerospace
- Category
- Data & Digital Tools
- Affiliations
- NIST Boulder
Description
NIST's cesium fountain primary frequency standards: NIST-F4 (under evaluation, approaching 10^-16 accuracy) and NIST-F3 (a high-uptime stable reference with drift below 10^-17/day), successors to NIST-F1/F2; laser-cooled cesium atoms tossed through a microwave cavity realize the SI second and contribute to UTC and UTC(NIST).
Official page
https://www.nist.gov/pml/time-and-frequency-division/time-realization/cesium-fountain-atomic-clocks
Open official page (opens in a new tab)Contact
- Contact
- Vladislav Gerginov <vladislav.gerginov@nist.gov> (303) 497-7366; Gregory Hoth <gregory.hoth@nist.gov> (303) 497-4414
Details
- Keywords
- primary frequency standard, laser cooling, si second, microwave cavity, hydrogen maser comparison
- Location
- Boulder, Colorado
- Location
- place named in page text: Boulder
- Standard id
- NIST-F3; NIST-F4
- Associated entity
- NIST
- Specifications
- This frequency is the natural resonance frequency of the cesium atom (9,192,631,770 Hz), or the frequency used to define the SI second.