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arXiv · 0803.0695

Matching NLLA+NNLO for event shape distributions

T. Gehrmann·G. Luisoni·H. Stenzel
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Abstract

We study the matching of the next-to-leading logarithmic approximation (NLLA) onto the fixed next-to-next-to-leading order (NNLO) calculation for event shape distributions in electron-positron annihilation. The resulting theoretical predictions combine all precision QCD knowledge on the distributions, and are theoretically reliable over an extended kinematical range. Compared to previously available matched NLLA+NLO and fixed order NNLO results, we observe that the effects of the combined NLLA+NNLO are small in the three-jet region, relevant for precision physics.

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T. Gehrmann, G. Luisoni, H. Stenzel. 2008-07-15. Matching NLLA+NNLO for event shape distributions. https://doi.org/10.1016/j.physletb.2008.05.023

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