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arXiv · 2209.13312

Determination of pion distribution amplitudes from the electromagnetic form factor with the data-driven dispersion relation

Jian Chai·Shan Cheng·Jun Hua
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Abstract

We study the pion electromagnetic form factor in the modulus squared dispersion relation, and do the model independent extraction of the most important nonperturbative parameters in pion light-cone distribution amplitude. The motivation of this work is the recent measurement of timelike form factor in the resonant regions, which makes up the piece lacking solid QCD-based calculation. With the perturbative QCD calculation up to next-to-leading-order QCD corrections and twist four level of meson distribution amplitudes, we obtain the chiral mass of pion meson as $m_0^\pi(1 \, {\rm GeV}) = 1.31^{+0.27}_{-0.30} \, {\rm GeV}$. More accuracy measurement of the timelike form factor are desirable to help us to determine the lowest gegenbauer moments in pion distribution amplitudes with the data-driven dispersion relation method developed in this work.

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Jian Chai, Shan Cheng, Jun Hua. 2022-09-27. Determination of pion distribution amplitudes from the electromagnetic form factor with the data-driven dispersion relation. https://doi.org/10.1140/epjc/s10052-023-11725-2

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