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arXiv · 2406.05591

High precision measurements of alpha_s at the future EIC

T. Kutz·J. R. Pybus·D. W. Upton·C. Cotton·A. Deshpande·A. Deur·W. B. Li·D. Nguyen·M. Nycz·X. Zheng
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Abstract

We present a projection study for the first moments of the inclusive spin structure function for the proton and neutron from simulated doubly-polarized e+p and e+3He collision data expected from the Electron-Ion collider. For detection and extraction of the neutron spin asymmetries from e+3He collisions, we used the double-tagging method which significantly reduces the uncertainty over the traditional inclusive method. Using the Bjorken sum rule, the projected results allow us to determine that the QCD coupling at the Z-pole alpha_s can be measured with a relative precision of 1.3%. This underscores the significance of the EIC for achieving precision determinations of alpha_s.

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T. Kutz, J. R. Pybus, D. W. Upton, C. Cotton, A. Deshpande, A. Deur, W. B. Li, D. Nguyen, M. Nycz, X. Zheng. 2024-06-08. High precision measurements of alpha_s at the future EIC. https://doi.org/10.1103/physrevd.110.074004

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