Resolution of X-Ray Rocking Curve Measurements Made with Finite Counting Statistics

We have analyzed the strain resolution of x-ray rocking curve profiles from measurements of the peak position and peak width made with finite counting statistics. In this work, we have considered x-ray rocking curves which may be Gaussian or Lorentzian in character and have analyzed the influence of the effective number of counts, full-width-at-half-maximum (FWHM) and the Bragg angle on the resolution. Often experimental resolution values are estimated on the order of 10⁻⁵ whereas this work predicts more sensitive values (10⁻⁹) with smaller FWHM and larger effective counts and Bragg angles.