{"paper":{"title":"Perturbative Effects in the Form Factor \\gamma\\gamma^*\\to \\pi and Extraction of the Pion Wave Function from CLEO Data","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"Alexander Schmedding, Oleg Yakovlev","submitted_at":"1999-05-18T22:01:18Z","abstract_excerpt":"We study the pion form factor F^{\\pi \\gamma\\gamma^*}(Q^2) in the light-cone sum rule approach, accounting for radiative corrections and higher twist effects.\n Comparing the results to the CLEO experimental data on F^{\\pi \\gamma\\gamma^*}(Q^2), we extract the the pion distribution amplitude of twist-2. The deviation of the distribution amplitude from the asymptotic one is small and is estimated to be a_2(\\mu) = 0.12 \\pm 0.03 at \\mu=2.4 GeV, in the model with one non-asymptotic term. The ansatz with two non-asymptotic terms gives some region of a_2 and a_4, which is consistent with the asymptotic"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/9905392","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}