{"paper":{"title":"Experimental status of the $\\pi\\pi$ isoscalar S wave at low energy: $f_0(600)$ pole and scattering length","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"F. J. Yndurain, J. R. Pelaez, R. Garcia-Martin","submitted_at":"2007-01-04T10:24:14Z","abstract_excerpt":"The experimental results obtained in the last few years on kaon decays (K$\\to2\\pi$ and, above all, Ke4 decays) allow a reliable, model independent determination of low energy $\\pi\\pi$ scattering in the S0 wave. Using them and, eventually, other sets of data, it is possible to give a precise parametrization of the S0 wave as well as to find the scattering length and effective range parameter. One can also perform an extrapolation to the pole of the \"$\\sigma$ resonance\" [$f_0(600)$]. We obtain the results $$a_0^{(0)}=0.233\\pm0.013 M^{-1}_\\pi,\\quad b_0^{(0)}=0.285\\pm0.012 M^{-3}_\\pi$$ and, for th"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/0701025","kind":"arxiv","version":3},"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/0701025/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"}