s******o 发帖数: 298 | 1 Making adjustments
Sullivan, Parker and other NIST physicists record precise seconds from the
cesium fountain clock for about a month, and then an average of these tiny
time frames is calculated to come up with the most perfect count of "one-one-
hundred."
This count, averaged with another from the French atomic fountain clock, keeps
the beat for what Parker calls the ensemble clock, compiled every month by the
French International Bureau of Weights and Measures. The ensemble clock is an
average |
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