Unpolarized GPDs at small x and non-zero skewness
Year: 2026
Type: article
Abstract: We study the small-$x$ asymptotics of unpolarized generalized parton distributions (GPDs) and generalized transverse momentum distributions (GTMDs). Unlike the previous works in the literature, we consider the case of non-zero (but small) skewness while allowing for non-linear contributions to the evolution equations. We show that unpolarized GPDs and GTMDs at small $x$ are related to the eikonal dipole amplitude $N$, whose small-$x$ evolution is given by the BK/JIMWLK evolution equations, and to the odderon amplitude $\cal O$, whose evolution is also known in the literature. We show that the effect of non-zero skewness $ξ\neq 0$ is to modify the value of the evolution parameter (rapidity) in the arguments for the dipole amplitudes $N$ and $\cal O$ from $Y = \ln (1/x)$ to $Y = \ln \min \left\{ 1/|x| , 1/|ξ| \right\}$.
Source: Physics Letters B
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
Awards: TAS::89 0222::TAS - NUCLEAR THEORY FOR HIGH ENERGY COLLISIONS; PI - ULRICH HEINZ, G1728142190, G1848180026, G208744781, G222768804, G2263355576, G2988778103, TOPICS IN THEORETICAL NUCLEAR PHYSICS, TOPICS IN THEORETICAL NUCLEAR PHYSICS, G51920480, TAS::89 0222::TAS - NUCLEAR THEORY FOR HIGH ENERGY COLLISIONS; PI - ULRICH HEINZ, G6427981414, G6674091005, TOPICS IN THEORETICAL NUCLEAR PHYSICS, G7520763071
OpenAlex ID: W4417293688