# Nucleon axial form factor from generalized parton distributions

## TL;DR

This paper calculates the nucleon axial form factor using generalized parton distributions derived from polarized PDFs, adjusting model parameters for better data fit and analyzing uncertainties in the predictions.

## Contribution

It introduces a method to compute the nucleon axial form factor from GPDs based on PDFs, with parameter tuning and uncertainty analysis.

## Key findings

- Adjusted model parameters improve data consistency.
- Quantified uncertainties in the axial form factor.
- Demonstrated the relation between GPDs and experimental data.

## Abstract

It is well established that the nucleon form factors can be related to Generalized Parton Distributions (GPDs) through sum-rules. On the other hand, GPDs can be expressed in terms of Parton Distribution Functions (PDFs) according to Diehl's model. In this work, we use this model to calculate polarized GPDs for quarks ($\widetilde{H}_q$) using the available polarized PDFs obtained from the experimental data, and then study the axial form factor of nucleon. We determine parameters of the model using standard $\chi^2$ analysis of experimental data. It is shown that some parameters should be readjusted, as compared to some previously reported values, to obtain better consistency between the theoretical predictions and experimental data. Moreover, we study in details the uncertainty of nucleon axial form factor due to various sources.