Pseudo and quasi gluon PDF in the BFKL approximation

TL;DR

This paper investigates the behavior of gauge-invariant gluon operators and their associated pseudo and quasi PDFs at low Bjorken x within the BFKL approximation, revealing significant differences and the role of higher twist corrections.

Contribution

It provides a detailed analysis of pseudo and quasi gluon PDFs at low x, highlighting their differences and the impact of higher twist corrections in the BFKL regime.

Findings

Pseudo-PDF and quasi-PDF differ significantly at low x.

Higher twist corrections in quasi-PDF scale as inverse powers of x_B P.

The study connects gluon operator behavior with low-x PDF approximations.

Abstract

I study the behavior of the gauge-invariant gluon bi-local operator with space-like separation at large longitudinal distances. Performing the Fourier transform, I also calculate the behavior of the pseudo and quasi gluon PDF at low Bjorken $x$ and compare it with the leading and next-to-leading twist approximation. I show that the pseudo-PDF and quasi-PDF are very different in this regime and that the higher twist corrections of the quasi-PDF come in not as inverse powers of $P$ but as inverse powers of $x_B P$.