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arXiv · 2302.07361

Empirical Determination of the Pion Mass Distribution

Yin-Zhen Xu·Khépani Raya·Zhu-Fang Cui·Craig D. Roberts·J. Rodríguez-Quintero
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Abstract

Existing pion+nucleus Drell-Yan and electron+pion scattering data are used to develop ensembles of model-independent representations of the pion generalised parton distribution (GPD). Therewith, one arrives at a data-driven prediction for the pion mass distribution form factor, $\theta_2$. Compared with the pion elastic electromagnetic form factor, $\theta_2$ is harder: the ratio of the radii derived from these two form factors is $r_\pi^{\theta_2}/r_\pi = 0.79(3)$. Our data-driven predictions for the pion GPD, related form factors and distributions should serve as valuable constraints on theories of pion structure.

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Yin-Zhen Xu, Khépani Raya, Zhu-Fang Cui, Craig D. Roberts, J. Rodríguez-Quintero. 2023-02-14. Empirical Determination of the Pion Mass Distribution. https://doi.org/10.1088/0256-307x%2F40%2F4%2F041201

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