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Inclusive electron-proton measurement prospects in the Electron-Ion Collider early science stage

Javier Jiménez-López*

Stephen Maple and Paul R. Newman

Katarzyna Wichmann

  • Vrije Universiteit Brussel, Brussels, Belgium

  • *Contact author: javiej09@ucm.es

Phys. Rev. D 114, 033002 – Published 11 August, 2026

DOI: https://doi.org/10.1103/424b-f9q3

Abstract

We explore the potential for extracting proton structure functions, proton parton density functions (PDFs), and the strong coupling αs(Mz2), using early science data from the future Electron-Ion Collider (EIC), both stand-alone, and in combination with data from the Hadron-Electron Ring Accelerator (HERA). Different scenarios are considered in which samples with modest luminosity are collected at either two or three EIC beam energy configurations. The Rosenbluth separation method is used to extract the proton structure functions F2 and FL from simulated data in a model-independent manner, showing that FL can be extracted significantly more precisely with three center-of-mass energies than with two, whilst also obtaining F2 to higher precision than has been achieved previously. The inclusion of a third beam configuration is also beneficial in the extraction of the strong coupling αs(Mz2) that is obtainable with unprecedented experimental precision with the early EIC data. Additionally, the precision of the proton PDFs is improved when adding these data, especially for large values of Bjorken-x, for both two and three EIC beam energy configurations. These studies show that EIC data will already be a highly competitive probe of perturbative quantum chromodynamics within the first five years of data taking.

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