Measurement of X-Ray Spectral Line Wavelengths by Using Two Bragg Reflections

Abstract

A novel method of measuring absolute x-ray wavelengths using simultaneous Bragg reflections at two parallel crystal plates of equal atomic spacing is presented. The accuracy of wavelength determination Δλ/λ for this method is discussed and a value of 5 × 10⁻⁵is achieved. Absolute wavelengths of L-shell laser-produced spectra of Cu, Ge, As, and Se and M-shell spectra of Gd and Tb have been measured in the wavelength region 7.5–8.5 Å using a quartz (10T0) quasimonolithic crystal blank.