Bremsstrahlung continuum

In an electron-excited X-ray spectrum the discrete X-ray lines are superimposed on a continuous background this is the well-known bremsstrahlung continuum ranging from 0 to the primary energy Eq of the electrons. The reason for this continuum is that because of the fundamental laws of electrodynamics, electrons emit X-rays when they are decelerated in the Coulomb field of an atom. As a result the upper energy limit of X-ray quanta is identical with the primary electron energy. 

XRF analysis using monochromatic excitation can provide a much better S/B than the polychromatic excitation for EDS and WDS XRF techniques described above by eliminating the scattering of bremsstrahlung (continuum X-rays) from the X-ray tube. Laboratory monochromatic XRF methods have been hindered by the lack of efficient X-ray focusing... 

The bremsstrahlung continuum is produced by electrons scattered by the atomic nuclei in the anode. In a small fraction of the cases where the electron is deflected... 

The first term in Eq. (3.7) represents the bremsstrahlung continuum expressed... 

As described in Chap. 3, a variety of excitation sources can be employed. With the wavelength-dispersive spectrometer where high source intensity is required, a high-power x-ray tube normally excites the specimen directly. Both the characteristic lines and the bremsstrahlung continuum from the x-ray tube are utilized. This... 

Hgure 1 Schematic representation of bremsstrahlung flux (( )), normalized bremsstrahlung continuum (/( )), and photocross-section ([Pg.32]

Since penetrating electrons in the anode of energy E higher than the binding energy Eq also eject corelevel electrons from the anode atoms, characteristic lines of the anode material are superimposed on the Bremsstrahlung continuum. The line-to-continuum intensity ratio is a function of atomic number of the... 

Sources emitting high-energy beta-particles are likely to give rise to a bremsstrahlung continuum at low energy. 

Like the resonance lines, the X-ray lines are always accompanied by satellites with intensities of up to 10% of that of the main line. This must be considered in the evaluation of spectra. For example, the small sUiictures seen at the low binding energy side of the photoelectron lines in Figs, la, 10c, and 14 are due to the satellites of the exciting radiation. In addition to the satellites, there is always a bremsstrahlung continuum underlying the characteristic X-ray lines. This continuum can be reduced by inserting a thin metal foil (the nature of which depends on the anode material) between the X-ray source and the collision chamber. The foil must be sufficiently thin and cannot be used to maintain a reasonable pressure difference between the source and the chamber. 

Measurements of the bremsstrahlung continuum during solar flares indicate that relativistic electrons are a... 

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