18-22 October 2021
Matsue, Shimane Prefecture, Japan
Asia/Tokyo timezone

Neutron Spin Structure from e-3He Scattering with Double Spectator Tagging at the Electron-Ion Collider

21 Oct 2021, 09:05
Room 303-304 (Kunibiki Messe)

Room 303-304

Kunibiki Messe

Parallel Session Presentation Future facilities and experiments Future facilities and experiments


Jackson Pybus (MIT)


This spin structure function of the neutron is traditionally determined by measuring the spin asymmetry of inclusive electron deep-inelastic scattering (DIS) off polarized $^3$He nuclei. In such experiments, correcting for nuclear effects can introduce large systematic uncertainties and model-dependencies. This talk presents our study of the feasibility of suppressing such model dependencies by tagging both spectator protons in the process of DIS off neutrons in $^3$He at the forthcoming Electron-Ion Collider (EIC). This allows us to reconstruct the momentum of the struck neutron to ensure it was nearly on-shell in the initial state, thereby reducing sensitivity to nuclear corrections, and to suppress contributions from electron DIS off protons in $^3$He. We find that the EIC can probe the neutron spin structure from $x_B$ of 0.003 to 0.0651. We further find that the double spectator tagging method results in reduced uncertainties by a factor of 4 on the extracted neutron spin asymmetries over all kinematics, and by a factor of 10 in the low-$x_B$ region, providing high-precision data that will give insight into the spin structure of the nucleon.

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