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arXiv · 2402.00255

The parity-odd structure function of nucleon from the Compton amplitude

K. U. Can·R. Horsley·Y. Nakamura·P. E. L. Rakow·G. Schierholz·H. Stüben·R. D. Young·J. M. Zanotti
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Abstract

The dominant contribution to the theoretical uncertainty in the extracted weak parameters of the Standard Model comes from the hadronic uncertainties in the electroweak boxes, i.e. $\gamma-W^\pm/Z$ exchange diagrams. A dispersive analysis relates the box diagrams to the parity-odd structure function, $F_3$, for which the experimental data either do not exist or belong to a separate isospin channel. Therefore a first-principles calculation of $F_3$ is highly desirable. In this contribution, we report on the QCDSF/UKQCD Collaboration's progress in calculating the moments of the $F_3^{\gamma Z}$ structure function from the forward Compton amplitude at the SU(3) symmetric point.

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K. U. Can, R. Horsley, Y. Nakamura, P. E. L. Rakow, G. Schierholz, H. Stüben, R. D. Young, J. M. Zanotti. 2024-02-01. The parity-odd structure function of nucleon from the Compton amplitude. https://arxiv.org/abs/2402.00255

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