Conveners
Nucleon spin and collinear structure at small-x
- Alexei Prokudin (Penn State Berks and JLab)
Description
co-host: David Richards
We present a Monte-Carlo-based analysis in the Jefferson Lab Angular Momentum (JAM) Collaboration framework of the combined world polarized deep-inelastic scattering (DIS) data at moderately small values of the Bjorken $x$ variable using spin-dependent quark dipoles. We demonstrate that the world data on the double-spin asymmetries $A_{||}$ and $A_1$ at $x<0.1$ can be successfully described...
We discuss the role of the chiral “triangle” anomaly in deeply inelastic scattering (DIS) of electrons off polarized protons employing a powerful worldline formalism which allows for the efficient computation of perturbative multi-leg Feynman amplitudes. We demonstrate how the triangle anomaly appears at high energies in the DIS "box diagram" for the polarized structure function $g_1(x_B,...
We discuss evolution of the small-x gluon helicity operator in the rapidity factorization approach. The operator is constructed from a polarized Wilson line with one non-eikonal local operator insertion and gives rise to gluon helicity TMDs at small x. To obtain the evolution equation for this operator we employ the background field method and derive the form of the leading sub-eikonal...
The small-$x$ quark helicity evolution equations at double-logarithmic order, with the kernel $\sim \alpha_s\ln^2 (1/x)$, had been derived previously, and the equations were solved analytically at large $N_c$ and numerically at large $N_c$ and $N_f$. (Here, $N_c$ and $N_f$ are the numbers of quark colors and flavors, respectively.) In this work, we derive the single-logarithmic corrections to...
Color charge correlations in the proton at moderately small x are extracted from its light-cone wave function. Charge fluctuations are far from Gaussian and the correlators exhibit non-trivial dependence on impact parameter as well as on the relative transverse momentum (or distance) of the gluon probes.
This analysis also provides initial conditions for small-x Balitsky-Kovchegov...
