{"paper":{"title":"A Study of Ultraviolet Renormalon Ambiguities in the Determination of $\\as$ from $\\tau$ Decay","license":"","headline":"","cross_cats":[],"primary_cat":"hep-ph","authors_text":"G. Altarelli (CERN), G. Ridolfi (CERN)., P. Nason (CERN)","submitted_at":"1995-01-09T11:23:47Z","abstract_excerpt":"The divergent large-order behaviour of the perturbative series relevant for the determination of $\\as$ from $\\tau$ decay is controlled by the leading ultraviolet (UV) renormalon. Even in the absence of the first infrared (IR) renormalon, an ambiguity of order $\\Lambda^2/m_\\tau^2$ is introduced. We make a quantitative study of the practical implications of this ambiguity. We discuss the magnitude of UV renormalon corrections obtained in the large-$N_f$ limit, which, although unrealistic, is nevertheless interesting to some extent. We then study a number of improved approximants for the perturba"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/9501240","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"}