Resummation of (-B(0) Alpha-s)**N Corrections to the Photon - Meson Transition Form-Factor Gamma* + Gamma ---> Pi0

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We have resummed all the (-b₀ alphaₛ)ⁿ contributions to the photon-meson transition form factor Fgamma pi. To do this, we have used the assumption of `naive nonabelianization' (NNA). Within NNA, a series in (Nf alfaₛ)ⁿ is interpreted as a series in (-b₀ alphaₛ)ⁿ by means of the restoration of the full first QCD beta-function coefficient -b₀ by hand. We have taken into account corrections to the leading order coefficient function and to the evolution of the distribution function. Due to conformal constraints, it is possible to find the eigenfunctions of the evolution kernel. It turns out that the nondiagonal corrections are small, and neglecting them we obtained a representation for the distribution function with multiplicatively renormalized moments. For a simple shape of the distribution function, which is close to the asymptotic shape, we find that the radiative correction decrease the LO by 30 % and the uncertainty in the resummation lies between 10 % and 2 % for Q² between 2 and 10 GeV².