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Apr 10 – 12, 2019
Denver, CO
US/Mountain timezone

The $g_2$ structure function and recent results from the SANE experiment

Apr 11, 2019, 5:15 PM
Director's Row J (Denver, CO)

Director's Row J

Denver, CO

Sheraton Denver Downtown Hotel, 1550 Court Pl. lobby level of the Plaza building


Whitney Armstrong (Argonne National Laboratory)


The Spin Asymmetries of the Nucleon Experiment (SANE) measured two double spin asymmetries using a polarized proton target and polarized electron beam at two beam energies, 4.7 GeV and 5.9 GeV. A large-acceptance open-configuration detector package identified scattered electrons at 40$^{\circ}$ and covered a wide range in Bjorken $x$ ($0.3 < x < 0.8$). Proportional to an average color Lorentz force, the twist-3 matrix element, $\tilde{d}_2^p$, was extracted from the measured asymmetries at $Q^2$ values ranging from 2.0 to 6.0 GeV$^2$. This talk will cover the status of the $g_2$ structure function and present the results for $\tilde{d}_2^p$ with a discussion of the puzzling scale dependence observed and future measurements.

Primary author

Whitney Armstrong (Argonne National Laboratory)

Presentation materials