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Subleading Power Resummation of Rapidity Logarithms: The Energy-Energy Correlator in $mathcal{N}=4$ SYM

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 نشر من قبل Gherardo Vita
 تاريخ النشر 2019
  مجال البحث
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We derive and solve renormalization group equations that allow for the resummation of subleading power rapidity logarithms. Our equations involve operator mixing into a new class of operators, which we term the rapidity identity operators, that will generically appear at subleading power in problems involving both rapidity and virtuality scales. To illustrate our formalism, we analytically solve these equations to resum the power suppressed logarithms appearing in the back-to-back (double light cone) limit of the Energy-Energy Correlator (EEC) in $mathcal{N}$=4 super-Yang-Mills. These logarithms can also be extracted to $mathcal{O}(alpha_s^3)$ from a recent perturbative calculation, and we find perfect agreement to this order. Instead of the standard Sudakov exponential, our resummed result for the subleading power logarithms is expressed in terms of Dawsons integral, with an argument related to the cusp anomalous dimension. We call this functional form Dawsons Sudakov. Our formalism is widely applicable for the resummation of subleading power rapidity logarithms in other more phenomenologically relevant observables, such as the EEC in QCD, the $p_T$ spectrum for color singlet boson production at hadron colliders, and the resummation of power suppressed logarithms in the Regge limit.

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