K-edge


Also found in: Wikipedia.

K-edge

a discontinuity in the absorption coefficient at an energy level corresponding to the binding energy of K-shell electrons.

K-edge

In radiography, the sharp increase in characteristic x-ray production resulting when the incoming x-ray beam matches the K-shell-binding energy of an atom. K-edge production can cause problems in predicting radiation exposure; i.e., when kilovolts peak is decreased and the K-edge is matched by the incoming x-ray photons, image density may increase.
References in periodicals archive ?
Iodine attenuation increases at lower tube potentials due to decreased Compton scattering and greater photoelectric effect when photon energy approaches the k-edge of iodine (33.
11) High keV levels are characterized by less image noise, while low energy levels, approaching the k-edge of iodine, are affected by more image noise, despite their quality, and are also characterized by higher contrast resolution.
Contract award notice: Purchase of 2 high-voltage generators for the X-ray tubes installed in the hybrid k-edge densitometry/XRF instrumentation in the laboratoire sur site at Areva NC plant La Hague (France)
Figure 2(b) displays the C K-edge XANES spectra of FLG and MWCNTs and the reference graphite.
Caption: FIGURE 2: Raman spectroscopy of (a) FLG and MWCNTs and C K-edge XANES spectroscopy of (b) FLG and MWCNTs along with graphite as a reference.
An experimental evaluation of the atomic photo effect cross section at K-edge can be carried out by an one of the following methods (i) measurement of K-X ray yield, following the ejection of photo electron, (ii) measurement of the photo electron intensities and (iii) extra polation method.
To supplement the data some of the atomic photo effect cross sections at different energies below K-edge were taken from the available literature (Veigele, 1973).
Figure 1 shows the images of silicon nanowires prepared by the top-down and the bottom-up method, and the Si K-edge XAFS revealing the crystalline nature of the nanostructures.
Figure 3 shows the XEOL and the S K-edge (1 s threshold) optical XAFS of a soft-template (dendrimer)-anchored CdS QD.
Lunar has taken its standard clinical technology using K-edge radiation sources and improved it enormously.
Contract notice:Purchase of 2 high-voltage generators for the X-ray tubes installed in the hybrid k-edge densitometry/XRF instrumentation in the laboratoire sur site at the Areva.
The degree that a material will attenuate the X-ray beam is dependent on (1) tissue composition and (2) photon energy level and how closely it exceeds the k-edge (ie, inner electron shell binding energy) of the material.