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Super-leading logarithms in non-global observables in QCD?

J. R. Forshaw·A. Kyrieleis·M. H. Seymour
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Abstract

We reconsider the calculation of a non-global QCD observable and find the possible breakdown of QCD coherence. This breakdown arises as a result of wide angle soft gluon emission developing a sensitivity to emission at small angles and it leads to the appearance of super-leading logarithms. We use the `gaps between jets' cross-section as a concrete example and illustrate that the new logarithms are intimately connected with the presence of Coulomb gluon contributions. We present some rough estimates of their potential phenomenological significance.

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J. R. Forshaw, A. Kyrieleis, M. H. Seymour. 2006-08-25. Super-leading logarithms in non-global observables in QCD?. https://doi.org/10.1088/1126-6708%2F2006%2F08%2F059

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