REVIEW OF MEASUREMENTS OF CRITICAL EXPONENT BETA IN SIMPLE MAGNETIC SYSTEMS

A critical review is given of measurements of the critical exponent β in three dimensional magnetic systems. Many claims of discrepancies between experimental data sets and between experiments and theory are either corrected or are found to be groundless on the basis of our reanalysis. A large percentage of the experiments are found to lie too far from the critical point to allow deduction of exponent values with uncertainties smaller than the differences between model calculation predictions. Those data which do allow deduction of exponent values appear to show a slight deviation from recent theoretical calculations.