{"paper":{"title":"QCD S Parameter from Inhomogeneous Bethe-Salpeter Equation","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"Masayasu Harada, Yuhsuke Yoshida","submitted_at":"1994-06-27T11:56:14Z","abstract_excerpt":"We calculate the low-energy parameter S in QCD, which is also known as L_{10}, and the pion decay constant f_\\pi using inhomogeneous Bethe-Salpeter equation in improved ladder approximation. To extract these quantities we calculate the ``V-A'' two-point function, \\Pi_{VV}(q^2) - \\Pi_{AA}(q^2), in space-like region. We obtain S = 0.43 \\sim 0.48, which is about 30% larger than the experimental value. The calculated f_\\pi is well consistent with the result by solving the homogeneous Bethe-Salpeter equation for pion. We also evaluate $S$ parameter in SU(3) gauge theory with N_D doublets of fermion"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/9406402","kind":"arxiv","version":1},"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"}