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Non-linear equation in the re-summed next-to-leading order of perturbative QCD: the leading twist approximation

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 نشر من قبل Eugene Levin
 تاريخ النشر 2020
  مجال البحث
والبحث باللغة English
 تأليف Carlos Contreras




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In this paper, we use the re-summation procedure, suggested in Refs.cite{DIMST,SALAM,SALAM1,SALAM2}, to fix the BFKL kernel in the NLO. However, we suggest a different way to introduce th non-linear corrections in the saturation region, which is based on the leading twist non-linear equation. In the kinematic region:$tau,equiv,r^2 Q^2_s(Y),leq,1$ , where $r$ denotes the size of the dipole, $Y$ its rapidity and $Q_s$ the saturation scale, we found that the re-summation contributes mostly to the leading twist of the BFKL equation. Assuming that the scattering amplitude is small, we suggest using the linear evolution equation in this region. For $tau ,>,1$ we are dealing with the re-summation of $Lb bas ,ln tauRb^n$ and other corrections in NLO approximation for the leading twist.We find the BFKL kernel in this kinematic region and write the non-linear equation, which we solve analytically. We believe the new equation could be a basis for a consistent phenomenology based on the CGC approach.

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