Flavor Asymmetries in the Proton and Semi-Inclusive Processes

TL;DR

This paper discusses how semi-inclusive electron scattering at future colliders can reveal detailed flavor asymmetries in the proton, including valence and sea quark distributions, through pion and heavy hadron production.

Contribution

It proposes utilizing extended kinematic coverage at the Electron-Polarized Ion Collider to measure flavor asymmetries in the proton with improved precision.

Findings

Potential to determine d/u ratio at large x

Ability to extract d-bar/u-bar ratio at small x

Probing strange and charm quark asymmetries

Abstract

Semi-inclusive electron scattering provides a powerful tool with which to study the spin and flavor distributions in the proton. Greater kinematic coverage at the proposed Electron-Polarized Ion Collider facility will enable the valence d/u ratio to be determined at large x through pion production. At small x, pion production can be used to extract the d-bar/u-bar ratio, complementing existing semi-inclusive measurements by HERMES, and Drell-Yan data from Fermilab. Asymmetries in heavier quark flavors can also be probed by tagging strange and charm hadrons in the final state.