Nonlinear gluon evolution in the color glass condensate: II Original Research Article

We complete the construction of the renormalization group equation (RGE) for the color glass condensate begun in Paper I. This is the equation which governs the evolution with rapidity of the statistical weight function for the color glass field. The coefficients in this equation—one-loop real and virtual contributions—are computed explicitly, to all orders in the color glass field. The resulting RGE can be interpreted as the imaginary-time evolution equation, with rapidity as the “imaginary time”, for a quantum field theory in two spatial dimensions. In the weak-field limit it reduces to the BFKL equation. In the general nonlinear case, it is equivalent to an equation by Weigert which summarizes in functional form the evolution equations for Wilson-line operators previously derived by Balitsky and Kovchegov.