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Cesium Cs
Where is cesium (caesium) used--or where does it impact our everyday lives?
Radioactive cesium-135 decays to barium-135 with beta decay:
135Cs --> 135Ba + e-
A cesium-37 sample has a half-life of 30 years. The sample is used to calibrate Geiger-Muller radioactivity meters
It radioactively decays by beta-particle emission
137Cs --> 137Ba + (-1)e
Sketch of a chip-sized atomic clock based on cesium vapor.
By Hailey L based on a NIST image (PD)
Cesium ion engine
Sketch by Alfie P, class of 2019, from WIkipedia Raisenan CC SA 3.0
Cesium was discovered spectroscopically, where light is split into characteriastic wavelengths. Here Chemistry One students are studying the spectra of lights and elements.
WIS Photographer
The atomic clock whcih is the timekeeper for the US Master Clock is at the U.S. Naval Observatory is barely two miles from Tregaron.
Link to the US Naval Observatory atomic clock site
The elements involved are rubidium and cesium
There are 4 rubidium fountain clocks and 19 5071 cesium clocks at the US Naval Observatory as well as 22 hydrogen maser clocks.
Rubidium atoms oscillate at about 6.8 billion times per second, and their frequency and stability can be measured to a precision of fractions of a trillionth of a second. Go to the link to discover more about rubidium time keeping
With cesium, a second was defined as the duration of 9,192,631,770 cycles of microwave light absorbed or emitted by the hyperfine transition of cesium-133 atoms in their ground state undisturbed by external fields. This information is from http://tycho.usno.navy.mil/cesium.html Go straight to the link for more information.
