Experimental Evaluation of the Scaling Function for the Scattered Intensity in the Critical Region

A new method has been developed for analyzing small-angle x-ray scattering data from fluids in the critical region without assuming the form of the angular distribution of the scattered intensity. By use of data obtained previously, the scaling function for the scattered intensity has been evaluated for argon. This function expresses the angular distribution of the scattering in terms of qξ, where ξ is the long-range correlation length, q=4πλ^-1sin(a/2), λ is the x-ray wavelength, and a is the scattering angle.