Fresh look at the nuclear transparency using the generalized parton distributions

TL;DR

This paper revisits nuclear transparency in QCD using generalized parton distributions, emphasizing the importance of proper definitions and the need for global analysis of nuclear data to better understand color transparency effects.

Contribution

It introduces a framework for calculating nuclear transparency with nGPDs and highlights the necessity of a global analysis for accurate theoretical predictions.

Findings

Nuclear transparency depends on the definition used.

Comparison with experimental data shows the importance of physical definitions.

A global analysis of nuclear data is crucial for reliable nGPDs.

Abstract

Color transparency (CT) is a fundamental phenomenon in QCD in which hadrons produced in high-energy exclusive processes traverse nuclear matter with minimal interactions. Nuclear transparency, which quantifies this attenuation suppression, is a quantity with high sensitivity to CT effects and provides critical insights into QCD dynamics in nuclear environments. In this study, we revisit nuclear transparency using the framework of generalized parton distributions (GPDs). By constructing nuclear GPDs (nGPDs) through the incorporation of nuclear parton distribution functions, we calculate the nuclear transparency $ T(Q^2) $ for the carbon nucleus as a function of momentum transfer $ Q^2 $ considering various definitions and compare the results obtained with available experimental data. Our finding highlights the importance of choosing a physically motivated definition of nuclear transparency. Moreover, we emphasize that a more reliable determination of nGPDs requires a dedicated global analysis incorporating nuclear data. Such an approach is essential for improving the theoretical understanding of CT and for achieving consistency with experimental observations in the high-$ Q^2 $ regime.