Interpolation between Sudakov and BFKL rapidity evolutions for TMD factorization at small $x$

Abstract

Within the framework of rapidity-only small-$x$ TMD factorization, the evolution with respect to the rapidity cutoff is initially governed by Sudakov double logarithms and subsequently by BFKL/BK single logarithms. The evolution equation proposed in this paper correctly reproduces both the Sudakov and BFKL limits, while providing a consistent interpolation between these two regimes.