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Some New Methods of Precision X-Ray Spectrometry*

Published online by Cambridge University Press:  06 March 2019

K. Das Gupta ,
Herbert Welch ,
P.F. Gott ,
John F. Priest ,
Sunny Cheng  and
Edmond Chu
K. Das Gupta
Affiliation:
Texas Tech University, Lubbock, Texas 79409
Herbert Welch
Affiliation:
Texas Tech University, Lubbock, Texas 79409
P.F. Gott
Affiliation:
Texas Tech University, Lubbock, Texas 79409
John F. Priest
Affiliation:
Texas Tech University, Lubbock, Texas 79409
Sunny Cheng
Affiliation:
Texas Tech University, Lubbock, Texas 79409
Edmond Chu
Affiliation:
Texas Tech University, Lubbock, Texas 79409
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Abstract

Three novel methods of x-ray spectrometry have been developed in recent years at Texas Tech University. These are:

  • 1. Three crystal spectrometer

  • 2. Two curved crystal spectrometer

  • 3. Spherically bent crystal spectrometer.

In this paper the new design features, and experimental results will be discussed to indicate the usefulness of the new instruments. The three crystal spectrometer is a modified two crystal instrument. A third crystal is used to analyze the output of the two crystal spectrometer. The first two crystals are operated as a standard two crystal spectrometer. The third crystal is swept through the spectrum transmitted by the first two crystals for each setting of the first two crystals. The peak intensity of the third crystal sweep corresponds to the energy setting of the two crystal spectrometer, and is the intensity used to plot the spectral lines. The two curved crystal spectrometer utilizes two transmission spectrographs with radii having a 2:1 ratio in series, the crystal with the smaller radius being set so that its focal point falls on the Rowland circle of the larger radius crystal, This instrument has a very low background intensity and is suitable for precision scattering and diffraetion work. The spherically bent crystal spectrometer makes use of high light gathering power and high orders of reflection to allow high resolution studies of weak spectral lines. It also has the advantage of ease of alignment and operation.

Type
Research Article
Information
Advances in X-Ray Analysis , Volume 16: 'Twenty-First Annual Conference on Applications of X-ray Analysis, August 2-4, 1972 , 1972 , pp. 251 - 259
Copyright
Copyright © International Centre for Diffraction Data 1972

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Footnotes

*

This work has been supported by the Robert A. Welch Foundation and AFOSR.

References

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