Abstract
In this paper, we review recent progress in the description of unpolarized transverse-momentum-dependent (TMD) gluon distributions at small x in the color glass condensate (CGC) effective theory. We discuss the origin of the nonuniversality of TMD gluon distributions in the TMD factorization framework and in the CGC theory and the equivalence of the two approaches in their overlapping domain of validity. We show some applications of this equivalence, including recent results on the behavior of TMD gluon distributions at small x, and on the study of gluon saturation. We discuss recent advances in the unification of the TMD evolution and the nonlinear small-x evolution of gluon distributions.
| Original language | English |
|---|---|
| Article number | 1830003 |
| Journal | International Journal of Modern Physics E |
| Volume | 27 |
| Issue number | 5 |
| DOIs | |
| Publication status | Published - May 2018 |
Funding
I would like to thank all of my collaborators from the projects covered in this review: Tolga Altinoluk, Néstor Armesto, Andreas van Hameren, Piotr Kotko, Alex Kovner, Krzysztof Kutak, Michael Lublinsky, Cyrille Marquet, Claude Roiesnel and Sebastian Sapeta. I thank Piet Mulders and Daniël Boer for many clarifying discussions on the subjects presented in this review. I thank Tom van Daal for his detailed reading of the draft and for his very useful feedback and discussions. I would like to thank the Nuclear Theory Group at the Brookhaven National Lab, where part of this review was presented, for their invitation and hospitality. I acknowledge support
| Funders | Funder number |
|---|---|
| Seventh Framework Programme | 320389 |
| European Commission |
Keywords
- CGC
- gluon saturation
- TMD factorization
- TMDs at small x