Unequal rapidity correlators in the dilute limit of JIMWLK

Abstract

We study unequal rapidity correlators in the stochastic Langevin picture of Jalilian-Marian– Iancu–McLerran–Weigert–Leonidov–Kovner (JIMWLK) evolution in the Color Glass Conden- sate effective field theory. By separately evolving the Wilson lines in the direct and complex conjugate amplitudes, we use the formalism to study two-particle production at large rapidity separations. We show that the evolution between the rapidities of the two produced particles can be expressed as a linear equa- tion, even in the full nonlinear limit. We also show how the Langevin formalism for two-particle correlations reduces to a BFKL picture in the dilute limit and in momentum space, providing an interpretation of BFKL evolution as a stochastic process for color charges.