Higher twist distribution amplitudes of the pion and electromagnetic form factorFπ(Q2)

S. S. Agaev
2005 Physical Review D  
The pion electromagnetic form factor is calculated within the QCD light-cone sum rule method and using a renormalon model for the higher twist distribution amplitudes (DAs). The theoretical predictions are compared with the experimental data and constraints on the pion leading and twist-4 DAs are extracted. An upper bound on the twist-4 contribution to the form factor and estimates of effects due to higher conformal spins in the pion twist-4 DAs are obtained.
doi:10.1103/physrevd.72.074020 fatcat:eqzj2fiodfalbfg6nofmsu35oi