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arXiv · 1501.00475

Non-global logarithms at finite Nc beyond leading order

Kamel Khelifa-Kerfa·Yazid Delenda
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Abstract

We analytically compute non-global logarithms at finite Nc fully up to 4 loops and partially at 5 loops, for the hemisphere mass distribution in e+e- to di-jets to leading logarithmic accuracy. Our method of calculation relies solely on integrating the eikonal squared-amplitudes for the emission of soft energy-ordered real-virtual gluons over the appropriate phase space. We show that the series of non-global logarithms in the said distribution exhibits a pattern of exponentiation thus confirming - by means of brute force - previous findings. In the large-Nc limit, our results coincide with those recently reported in literature. A comparison of our proposed exponential form with all-orders numerical solutions is performed and the phenomenological impact of the finite-Nc corrections is discussed.

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Kamel Khelifa-Kerfa, Yazid Delenda. 2015-03-25. Non-global logarithms at finite Nc beyond leading order. https://doi.org/10.1007/jhep03(2015)094

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