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arXiv · 2609.00230

Probing Dense Nuclear Matter at Small-x: A workflow for a global analysis framework

Abstract

The dipole model provides a powerful framework for describing high-energy nuclear interactions, particularly in the regime of dense gluonic matter. However, accurately evolving the dipole--nucleus scattering amplitude remains a major computational challenge because it is governed by nonlinear QCD evolution equations. To address this, we investigate a machine learning (ML) model as an efficient surrogate for the conventional numerical evolution. These ML-based approximations dramatically reduce the computational cost of global analyses while maintaining the accuracy required to describe a broad range of experimental data. We systematically evaluate the ML results for accuracy, computational efficiency, and ability to capture essential features of dipole evolution in nuclear environments. These computational advancements will enable global analyses of diverse datasets within both the dipole and parton model frameworks, providing a more rigorous probe of nuclear structure in the dense regime. Comparing both descriptions within a common fitting framework can provide precise constraints on the gluon distributions and advance our understanding of the quark and gluon structure of nuclei, particularly in the small-x region.

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Junaid S. Khan, Rebecca L. Lustberg, Fredrick Olness, Peter Risse, Bjoern Schenke, Brandon Stevenson. 2026-09-10. Probing Dense Nuclear Matter at Small-x: A workflow for a global analysis framework. https://arxiv.org/abs/2609.00230

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