Physical Review D
The small-𝔁 deep inelastic scattering in the saturation region is governed by the nonlinear evolution of Wilson-lines operators. In the leading logarithmic approximation it is given by the Balitsky-Kovchegov (BK) equation for the evolution of color dipoles. In the next-to-leading order (NLO) the nonlinear equation gets contributions from quark and gluon loops. In this paper I calculate the quark-loop contribution to small-𝔁 evolution of Wilson lines in the NLO. It turns out that there are no new operators at the one-loop level—just as at the tree level, the high-energy scattering can be described in terms of Wilson lines. In addition, from the analysis of quark loops I find that the argument of coupling constant in the BK equation is determined by the size of the parent dipole rather than by the size of produced dipoles. These results are to be supported by future calculation of gluon loops.
Original Publication Citation
Balitsky, I. (2007) Quark contribution to the small-𝔁 evolution of color dipole. Physical Review D., 75(1),1-21, Article 014001. https://doi.org/10.1103/PhysRevD.75.014001
Balitsky, Ian, "Quark Contribution to the Small-𝔁 Evolution of Color Dipole" (2007). Physics Faculty Publications. 606.