Electromagnetic Pion Form Factor and Neutral Pion Decay Width
نویسنده
چکیده
The electromagnetic pion form factor, Fπ(q 2), is calculated for spacelike-q2 in impulse approximation using a confining quark propagator, S, and a dressed quarkphoton vertex, Γμ, obtained from realistic, nonperturbative Dyson-Schwinger equation studies. Good agreement with the available data is obtained for Fπ(q 2) and other pion observables, including the decay π0 → γ γ. This calculation suggests that soft, nonperturbative contributions dominate Fπ(q 2) at presently accessible q2.
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تاریخ انتشار 1994