{"paper":{"title":"Measurement of the $\\Lambda_b$ polarization and angular parameters in $\\Lambda_b\\to J/\\psi\\, \\Lambda$ decays from pp collisions at $\\sqrt{s}=$ 7 and 8 TeV","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"hep-ex","authors_text":"CMS Collaboration","submitted_at":"2018-02-13T21:37:51Z","abstract_excerpt":"An analysis of the decay $\\Lambda_b \\to J/\\psi(\\to\\mu^+\\mu^-)\\Lambda(\\to p \\pi^-)$ decay is performed to measure the $\\Lambda_b$ polarization and three angular parameters in data from pp collisions at $\\sqrt{s} =$ 7 and 8 TeV, collected by the CMS experiment at the LHC. The $\\Lambda_b$ polarization is measured to be 0.00 $\\pm$ 0.06 (stat) $\\pm$ 0.06 (syst) and the parity-violating asymmetry parameter is determined to be 0.14 $\\pm$ 0.14 (stat) $\\pm$ 0.10 (syst). The measurements are compared to various theoretical predictions, including those from perturbative quantum chromodynamics."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1802.04867","kind":"arxiv","version":2},"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"}