Precision Studies of the Neutron Spin Structure g₂ⁿ using a Polarized Helium-3 Target at Jefferson Lab

The energy and spectrometer upgrades at Jefferson Lab have opened new opportunities to study the spin structure of the nucleon in previously unexplored kinematic regions. The A₁ⁿ/g₂ⁿ collaboration has performed precision measurements of the spin-structure functions g₁ⁿ and g₂ⁿ over a wide range of Bjorken-x (0.20 < x_Bj < 0.95) in inclusive polarized electron scattering from a polarized helium-3 target in Hall C. The goal of the experiment is to extract the Q² dependence of the twist-3 matrix element d₂ⁿ, which represents the third moment in

x_Bj of a specific combination of g₁ⁿ and g₂ⁿ. This quantity is dominated by quark–gluon correlations and thus provides a measure of where scattering from incoherent quarks breaks down. For the first time, d₂ⁿ will be evaluated at two different Q² values (3.0 GeV² < Q² < 5.6 GeV²), with Q² held nearly constant over a broad range of x_Bj. Details of the experiment and an update on the data analysis will be presented.