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arXiv · hep-ph/9905339

Non-perturbative effects in the energy-energy correlation

Yu. L. Dokshitzer·G. Marchesini·B. R. Webber
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Abstract

The fully resummed next-to-leading-order perturbative calculation of the energy-energy correlation in $e^+e^-$ annihilation is extended to include the leading non-perturbative power-behaved contributions computed using the ``dispersive method'' applied earlier to event shape variables. The correlation between a leading (anti)quark and a gluon produces a non-perturbative 1/Q contribution, while non-perturbative effects in the quark-antiquark correlation give rise to a smaller contribution $\ln Q^2/Q^2$. In the back-to-back region, the power-suppressed contributions actually decrease much more slowly, as small non-integer powers of 1/Q, as a result of the interplay with perturbative effects. The hypothesis of a universal low-energy form for the strong coupling relates the coefficients of these contributions to those measured for other observables.

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Yu. L. Dokshitzer, G. Marchesini, B. R. Webber. 1999-05-14. Non-perturbative effects in the energy-energy correlation. https://doi.org/10.1088/1126-6708%2F1999%2F07%2F012

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