{"paper":{"title":"The Hyperfine Splitting in Charmonium: Lattice Computations Using the Wilson and Clover Fermion Actions","license":"","headline":"","cross_cats":[],"primary_cat":"hep-lat","authors_text":"A.D. Simpson, B.J. Pendleton, C. Michael, C.T. Sachrajda, D.G. Richards, D.S. Henty, J.N. Simone, K.C. Bowler, P.W. Stephenson, R.D. Kenway, S.P. Booth, UKQCD Collaboration: C.R. Allton","submitted_at":"1992-08-21T09:22:18Z","abstract_excerpt":"We compute the hyperfine splitting $m_{J/\\psi}-m_{\\eta_c}$ on the lattice, using both the Wilson and $O(a)$-improved (clover) actions for quenched quarks. The computations are performed on a $24^3\\times48$ lattice at $\\beta = 6.2$, using the same set of 18 gluon configurations for both fermion actions. We find that the splitting is 1.83\\err{13}{15} times larger with the clover action than with the Wilson action, demonstrating the sensitivity of the spin-splitting to the magnetic moment term which is present in the clover action. However, even with the clover action the result is less than half"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-lat/9208018","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"}