linewidth
Noun
Meaning
English Wikipedia has an article on:spectral linewidthWikipedia
linewidth (plural linewidths)
(physics) A measure of the width of the band of frequencies of radiation emitted or absorbed in an atomic or molecular transition; a result of the uncertainty principle.
Examples
Additional recoil energy is also lost during absorption, so in order for resonance to occur the recoil energy must actually be less than half the linewidth for the corresponding nuclear transition.
By careful design of the laser components, the purity of the laser light (measured as the " linewidth ") can be improved more than the purity of any other light source.
The evidence comes from the fact that the "turbulent" velocities inferred from CO linewidth scale in the same manner as the orbital velocity (a virial relation).
A single mode fiber laser has a linewidth of a few kHz.
Fast-decaying states have a broad linewidth, while slow decaying states have a narrow linewidth.
Hydrogen masers have linewidth around 1 Hz; http://www.physics.harvard.edu/Thesespdfs/humphrey.pdf - Precision measurements with atomic hydrogen masers their coherence length approximately corresponds to the distance from the Earth to the Moon.