Caesium standard - Wikipedia
Caesium atomic clocks are one of the most accurate time and frequency standards, and serve as the primary standard for the definition of the second in the International System of Units (SI), the modern metric system.
How does one arrive at the exact number of cycles of radiation a cesium …
2002年12月16日 · In a collaboration between Essen and Markowitz, the relative durations of the astronomical and atomic (cesium) seconds were measured over an averaging time of 2.75 years with a final...
Atomic Clocks Use Quantum Timekeeping | Scientific American
2010年3月31日 · The "ticks" of the current standard atomic clocks are marked by the regular vibrations of an ensemble of cesium atoms, which vibrate 9.2 billion times every second. However, noise inherent in...
How Does a Practical Cesium Atomic Clock Work? - HowStuffWorks
To turn the cesium atomic resonance into an atomic clock, it is necessary to measure one of its transition or resonant frequencies accurately. This is normally done by locking a crystal oscillator to the principal microwave resonance of the cesium atom.
How many vibrations of a cesium atom equal one second?
2024年5月24日 · 9,192,631,770 vibrations of a cesium atom equal one second. This forms the basis of the definition of one second in the International System of Units (SI) based on the cesium...
ELI5: Why was Cesium-133 atom chosen for defining "1 second ... - Reddit
2021年8月27日 · It’s more accurate to say “high number of vibrations per second”. If you use each vibration as 1 tick of a clock, then the more ticks per second means you can be more accurate in a time measurement.
Cesium Time - The New York Times
2007年5月8日 · As the microwaves hit, the outermost electron jumps from a lower orbit to a higher orbit and then back, absorbing and releasing packets of light energy that can be measured. The exact speed of this...
quantum mechanics - Oscillation of Atom - Physics Stack Exchange
2015年8月31日 · The Cesium atom itself is not oscillating. The oscillation being measured is the frequency of the photon that is emitted by the Cesium valence electron when it jumps from an excited energy state back down to the ground energy state.
NIST Launches a New U.S. Time Standard: NIST-F2 Atomic Clock
2014年4月3日 · Both NIST-F1 and NIST-F2 measure the frequency of a particular transition in the cesium atom—which is 9,192,631,770 vibrations per second, and is used to define the second, the international (SI) unit of time.
In a collaboration between Essen and Markowitz, the relative durations of the astronomical and atomic (cesium) seconds were measured over an averaging time of 2.75 years with a final determination that the cesium frequency was 9,192,631,770 ± 20 Hz.