a Precision Calculation of the Next-To Order Energy-Energy Correlation Function

The next-to-leading order perturbative contribution to the Energy-Energy Correlation function (EEC) of the annihilation of electrons and positrons into hadrons has been calculated by six collaborations, most recently by Stephen Ellis and this author. The Clay and Ellis calculation was performed to high precision and the results are shown to be larger than previously reported. The extreme accuracy of the reproduction of the predictions of the leading logarithm approximation and the precision of the cancellation of infrared singularities exhibited by this new calculation suggest that it is reliable. Evidence also suggests that the source of the disagreement with previous results lies in the regulation of double infrared singularities. Potential weaknesses of the standard methods for control of such singularities are explored, and the Clay and Ellis calculation is shown to survive tests for such weaknesses. The results of the Clay and Ellis calculation are analyzed in terms of their implications for future calculations as well as for experimental measurements of the EEC and other observables.