Bézier curve parametrization for pion PDFs*

We introduce a new method to improve the determination of probability densities in particle physics, utilizing the Fantômas4QCD tool. Our approach uses Bézier curve fitting, which reduces computational power requirements by employing interpolation, making it a less resource-intensive option compared to machine learning or AI techniques. By incorporating this method into the xFitter package, we conducted a comprehensive study of the pion's internal structure, marking the first analysis to consider how the choice of functional form influences uncertainty in the results.