Study pion distribution amplitudes from the electromagnetic form factor by data-driven dispersion relation

Abstract We study the pion electromagnetic form factor in modulus squared dispersion relation, and do model independent extraction of chiral mass embedded sub-leading twist light-cone distribution amplitude. The motivation this work is recent measurement timelike resonant regions, which makes up piece lacking solid QCD-based calculation. With perturbative QCD calculation to next-to-leading-order strong coupling four level meson amplitudes, we obtain as $$m_0^\pi (1 \, \textrm{GeV}) = 1.31^{+0.27}_{-0.30} \textrm{GeV}$$ m 0 π ( 1 GeV ) = . 31 - 0.30 + 0.27 . Due enhancement contribution from amplitudes calculation, can not extract lowest Gegenbauer moments factor. This problem could be settled down with foresee Belle-II BESIII transition especially large momentum transfers regions.