Pion distribution amplitude – from theory to data
نویسندگان
چکیده
We describe the present status of the pion distribution amplitude as originated from two sources: (i) a nonperturbative approach, based on QCD sum rules with nonlocal condensates, and (ii) a NLO QCD analysis of the CLEO data on Fγγ ∗π(Q2), supplemented by the E791 data on diffractive dijet production, and the JLab F(pi) data on the pion electromagnetic form factor. 1. PION DISTRIBUTION AMPLITUDE FROM QCD SUM RULES The pion distribution amplitude (DA) can be defined through the matrix element of a nonlocal axial current on the light cone 〈0 | d̄(z)γμγ5C (z,0)u(0) | π(P)〉 ∣
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تاریخ انتشار 2004