{"paper":{"title":"Mixed quark-gluon condensate from instantons","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"C. Weiss (Ruhr-Univ. Bochum), M.V. Polyakov","submitted_at":"1996-07-04T22:12:45Z","abstract_excerpt":"We calculate the vacuum expectation value of the dimension-5 \"mixed\" quark-gluon operator, $O_\\sigma = \\bar\\psi (\\lambda^a /2) \\sigma_{\\mu\\nu} \\psi F_{\\mu\\nu}^a$, in the instanton vacuum. Within the $1/N_c$--expansion the QCD operator is replaced by an effective many-fermion operator, which is averaged over the effective theory of massive quarks derived from instantons. We find $m_0^2 \\equiv \\langle O_\\sigma \\rangle / \\langle \\bar\\psi\\psi \\rangle \\approx 4 \\bar\\rho^{-2} = 1.4 GeV^2$, somewhat larger than the estimate from QCD sum rules for the nucleon."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/9607244","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/hep-ph/9607244/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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"}