{"paper":{"title":"The gluonic condensate from the hyperfine splitting $M_{\\rm cog}(\\chi_{cJ})-M(h_c)$ in charmonium","license":"","headline":"","cross_cats":["hep-ex"],"primary_cat":"hep-ph","authors_text":"A.M. Badalian (State Research Center, Amsterdam, Department of Physics, Experimental Physics, Institute of Theoretical, Moscow, Russia) B.L.G. Bakker (Vrije Universiteit, the Netherlands)","submitted_at":"2004-12-02T11:35:50Z","abstract_excerpt":"The precision measurement of the hyperfine splitting $\\Delta_{\\rm HF} (1P, c\\bar c)=M_{\\rm cog} (\\chi_{cJ}) - M(h_c) = -0.5 \\pm 0.4$ MeV in the Fermilab--E835 experiment allows to determine the gluonic condensate $G_2$ with high accuracy if the gluonic correlation length $T_g$ is fixed. In our calculations the negative value of $\\Delta_{\\rm HF} = -0.3 \\pm 0.4$ MeV is obtained only if the relatively small $T_g = 0.16$ fm and $G_2 = 0.065 (3)$ GeV${}^4$ are taken. These values correspond to the ``physical'' string tension $(\\sigma \\approx 0.18 $ GeV$^2$). For $T_g \\ge 0.2$ fm the hyperfine split"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/0412030","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"}