Self-consistent determination of proton and nuclear PDFs at the Electron Ion Collider

Rabah Abdul Khalek,Jacob J Ethier,Juan Rojo,Emanuele R Nocera

doi:10.1103/physrevd.103.096005

Abstract

We quantify the impact of unpolarized lepton-proton and lepton-nucleus inclusive deep-inelastic scattering (DIS) cross section measurements from the future Electron-Ion Collider (EIC) on the proton and nuclear parton distribution functions (PDFs). To this purpose, we include neutral- and charged-current DIS pseudodata in a self-consistent set of proton and nuclear global PDF determinations based on the NNPDF methodology. We demonstrate that the EIC measurements will reduce the uncertainty of the light quark PDFs of the proton at large values of the momentum fraction $x$ and, more significantly, of the quark and gluon PDFs of heavy nuclei, especially at small and large $x$. We illustrate the implications of the improved precision of nuclear PDFs for the interaction of ultrahigh energy cosmic neutrinos with matter.

Highlights

The construction of an Electron Ion Collider (EIC) [1,2] has been recently approved by the United States Department of Energy at Brookhaven National Laboratory and could record the first scattering events as early as 2030
In particular we study how such data could improve the determination of the unpolarized proton and nuclear parton distribution functions (PDFs) [3] by incorporating suitable pseudodata in a self-consistent set of PDF fits based on the NNPDF methodology
We have quantified the impact that unpolarized lepton-proton and lepton-nucleus inclusive deep-inelastic scattering (DIS) cross section measurements at the future Electron-Ion Collider (EIC) will have on the unpolarized proton and nuclear PDFs

Summary

Introduction

By colliding (polarized) electron or positron beams with proton or ion beams for a range of center-of-mass energies, the EIC will perform key measurements to investigate QCD at the intensity frontier. These measurements will be fundamental to understand how partons are distributed in position and momentum spaces within a proton, how the proton spin originates from the spin and the dynamics of partons, how the nuclear medium modifies partonic interactions, and whether gluons saturate within heavy nuclei. We focus on one important class of EIC measurements, namely inclusive cross sections for unpolarized lepton-proton and lepton-nucleus deep-inelastic scattering (DIS). The unique ability of an EIC to measure inclusive DIS cross

Methods

Results

Conclusion