Charm and longitudinal structure functions with the Kharzeev-Levin-Nardi model

TL;DR

This paper applies the Kharzeev-Levin-Nardi model to fit HERA data on charm and longitudinal structure functions, demonstrating its effectiveness and predictive power for future electron-ion collider experiments.

Contribution

It shows that the KLN model accurately describes existing data and can be used to predict structure functions for upcoming collider measurements.

Findings

The KLN model fits HERA data well.

Predictions for future electron-ion collider measurements.

The model interpolates between other nuclear gluon distribution models.

Abstract

We use the Kharzeev-Levin-Nardi model of the low $x$ gluon distributions to fit recent HERA data on charm and longitudinal structure functions. Having checked that this model gives a good description of the data, we use it to predict $F^c_2$ and $F_L$ to be measured in a future electron-ion collider. The results interpolate between those obtained with the de Florian-Sassot and Eskola-Paukkunen-Salgado nuclear gluon distributions. The conclusion of this exercise is that the KLN model, simple as it is, may still be used as an auxiliary tool to make estimates both for heavy ion and electron-ion collisions.