Coherent forward scattering atomic

In a system for coherent forward scattering, the radiation of a primary source is led through the atom reservoir (a flame or a furnace), across which a magnetic field is applied. When the atom reservoir is placed between crossed polarizers scattered signals for the atomic species occur on a zero-background. When a line source such as a hollow cathode lamp or a laser is used, determinations of the respective elements can be performed. In the case of a continuous source, such as a xenon lamp, and a multichannel spectrometer simultaneous multielement determinations can also be performed. The method is known as coherent forward scattering atomic spectrometry [309, 310]. This approach has become particularly interesting since flexible multichannel diode array spectrometers have became available. 

Yamamoto M., Murayama S., Ito M. and Yasuda M. (1980) Theoretical basis for multielement analysis by coherent forward scattering atomic spectroscopy Spectrochim Acta, Part B 35 43-50. 

ESCA electron spectroscopy for chemical analysis (X-ray photoelectron spectroscopy) ESI electrospray ionization ET-AAS (Also denoted GFAAS, EAAS, EA-AAS, ETAAS, ETA-AAS) electrothermal atomization atomic absorption spectrometry ETA-CFS electrothermal atomization -coherent forward scattering (atomic magneto-optic rotation) spectrometry ETAES electrothermal atomization atomic emission spectrometry ETAES electrothermal atomization atomic fluorescence spectrometry ETA-LEI electrothermal atomization -laser enhanced ionization spectrometry... 

Coherent forward scattering atomic spectrometry is a multielement method. The instrumentation required is simple and consists of the same components as a Zeeman AAS spectrometer. As the spectra contain only a few resonance lines, a spectrometer with low spectral resolution is sufficient. The detection limits depend considerably on the primary source and on the atomizer. With a xenon lamp as primary source, multielement determinations can be performed, but the power of detection is low as the spectral radiances are low compared with those of a hollow cathode lamp. By using high-intensity laser sources, the intensities of the signals and the power of detection can be considerably improved. When furnaces are used as atomizers, typical detection limits in the case of a xenon arc are Cd 4 ng pb 0.9 T1 1.5 Fe 2.5 and Zn 50 ng [ 188]. These are considerably higher than in furnace AAS. 

Coherent forward scattering (CFS) atomic spectrometry is a multi-element method. The instrumentation required is simple and consists of the same components as a... 

Eq. (3.26). Now diffractive scattering occurs in a very narrow forward cone (assuming the atoms are not moving too slowly) and so the accompanying velocity changes are small. Let dv be the characteristic value of the velocity change v - v in the diffractive region. A coherence which is prepared at time t = 0 will subse-... 

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