# Inverse Radon transform at work

## TL;DR

This paper explores the application of the inverse Radon transform to derive partonic double distributions from generalized parton distributions, comparing numerical methods and extending theoretical understanding.

## Contribution

It introduces an extension of generalized parton distributions via dual parts and compares filtered backprojection with single integral transforms for numerical evaluation.

## Key findings

- Filtered backprojection effectively reconstructs double distributions.
- Single integral transforms are valid without wave function overlap representation.
- Numerical evaluations show consistency between methods.

## Abstract

The inverse Radon transform allows to obtain partonic double distributions from (extended) generalized parton distributions. We express the extension of generalized parton distributions by their dual parts, generalized distribution amplitudes and study some aspects of the filtered backprojection (inverse Radon transform). We also show that single integral transforms, previously obtained in the context of wave function overlap representation, are valid for generalized parton distributions that do not possess such a representation. Utilizing Radyushkin`s double distribution ansatz, we study and compare the numerical evaluation of double distributions within the filtered backprojection and single integral transforms along the imaginary and real axes.