Pion form factor analysis using NLO analytic perturbation theory
نویسنده
چکیده
I present results for the pion’s electromagnetic form factor in the spacelike region, which implement the most advanced perturbative information currently available for this observable in conjunction with a pion distribution amplitude that agrees with the CLEO data on the pion-photon transition form factor at the 1σ level. I show that using for the running strong coupling and its powers their analytic versions in the sense of Shirkov and Solovtsov, the obtained predictions become insensitive to the renormalization scheme and scale setting adopted. Joining the hard contribution with the soft part on account of local duality and respecting the Ward identity at Q = 0, the agreement with the available experimental data, including expectations from planned experiments at JLab, is remarkable both in trend and magnitude. I also comment on Sudakov resummation within the analytic approach.
منابع مشابه
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