Pion form factors at intermediate momentum transfer in a covariant approach
نویسندگان
چکیده
We study the pion electromagnetic and γ + π0 → γ transition form factors at intermediate momentum transfer. We calculate soft, nonperturbative corrections to the leading perturbative amplitudes which arise from the qq̄component of the pion wave function. We work in Minkowski space and use a Lorentz covariant, gauge-invariant generalized perturbative integral representation for the qq̄ amplitudes. For the transition form factor we find relative insensitivity to the detailed nonperturbative structure of the wavefunction for |q2| ∼ > 10 GeV2, whereas considerable sensitivity is found for the electromagnetic form factor. 12.38.Aw, 12.38.Lg, 12.40-y Typeset using REVTEX 1
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