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arXiv · 1607.02153

Small-$x$ resummation from HELL

Abstract

Small-$x$ logarithmic enhancements arising from high-energy gluon emissions affect both the evolution of collinearly-factorized parton densities and partonic coefficient functions. With the higher collider energy reached by the LHC, the prospect of a future high-energy collider, and the recent deep-inelastic scattering (DIS) results at small-$x$ from HERA, providing phenomenological tools for performing small-$x$ resummation has become of great relevance. In this paper we discuss a framework to perform small-$x$ resummation for both parton evolution and partonic coefficient functions and we describe its implementation in a computer code named High-Energy Large Logarithms (HELL). We present resummed and matched results for the DGLAP splitting functions and, as a proof of principle, for the massless structure functions in DIS.

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Marco Bonvini, Simone Marzani, Tiziano Peraro. 2016-10-28. Small-$x$ resummation from HELL. https://doi.org/10.1140/epjc%2Fs10052-016-4445-6

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