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X-Ray Spectroscopy

  1. Thomas H. Markert†1,
  2. Eckhart Förster2

Published Online: 15 DEC 2009

DOI: 10.1002/3527600434.eap464.pub3

Encyclopedia of Applied Physics

Encyclopedia of Applied Physics

How to Cite

Markert†, T. H. and Förster, E. 2009. X-Ray Spectroscopy. Encyclopedia of Applied Physics. 89–113.

Author Information

  1. 1

    Center for Space Research, Cambridge, MA, USA

  2. 2

    Friedrich Schiller University, X-Ray Optics Group, Institute of Optics and Quantum Electronics, Jena, Germany

Publication History

  1. Published Online: 15 DEC 2009


X-ray spectrometers are used in many fields of pure and applied science as well as in industry. They are employed to investigate cosmic and laboratory high-temperature plasmas where high spectral resolution in the emission spectra is required. Commercial X-ray spectrometers register X-ray fluorescence of a sample under X-ray irradiation or electron bombardment. In this case, registration of a wide spectral range with moderate resolution is performed to obtain the elemental composition of a sample.

The main experimental parameters of a spectrometer are its resolving power, sensitivity, and breadth of spectral coverage. Dispersive spectrometers that use X-ray crystal diffraction to spread out the incident spectrum have great advantages in spectral resolution. To increase their sensitivity, different X-ray optics such as grazing incident mirrors, polycapillaries, bent gratings, or bent crystals are implemented. Nondispersive spectrometers that convert the energy of an incident X-ray photon into a number of “particles” (electron-hole pairs, electron-ion pairs, phonons, etc.) have a moderate spectral resolution, good sensitivity, and wide breadth of spectral coverage. Recently developed microcalorimeters need a complex cryogenic system for the detector, but their spectral resolution is competitive with dispersive spectrometers. In industry, small spectrometers equipped with air-cooled X-ray minitubes and adapted focusing optics now compete with mature designs of X-ray spectrometers with powerful, water-cooled X-ray tubes.


  • crystal spectrometers;
  • diffraction gratings;
  • microcalorimeters;
  • multilayers;
  • semiconductor detectors;
  • X-ray detectors;
  • X-ray imaging;
  • X-ray spectrometry