Meaning of absorption edge

absorp'tion edge"

Pronunciation: [key]
— Physics. Physics.
  1. a discontinuity in the graph of the absorption coefficient of a substance plotted against the wavelength of x-rays being absorbed, representing the minimum energy necessary to free electrons from particular shells of the atoms of the substance. Also called
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.