forbidden lines


forbidden lines
forbidden lines,
Physics. spectral lines of radiation produced by changes in energy level that occur within an atom only when the interval between atomic collisions is exceptionally long: »

They are the so-called forbidden lines—colors which an atom is extremely reluctant to radiate and will not radiate at all unless left undisturbed by collisions for seconds or minutes at a time (Armin J. Deutsch).


Useful english dictionary. 2012.

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