{"paper":{"title":"First measurement of prompt and non-prompt ${\\rm D^{*+}}$ vector meson spin alignment in pp collisions at $\\sqrt{s} = 13$ TeV","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":["hep-ex"],"primary_cat":"nucl-ex","authors_text":"ALICE Collaboration","submitted_at":"2022-12-13T14:03:10Z","abstract_excerpt":"This letter reports the first measurement of spin alignment, with respect to the helicity axis, for ${\\rm D^{*+}}$ vector mesons and their charge conjugates from charm-quark hadronisation (prompt) and from beauty-meson decays (non-prompt) in hadron collisions. The measurements were performed at midrapidity ($|y|<0.8$) as a function of transverse momentum ($p_{\\rm T}$) in proton-proton (pp) collisions collected by ALICE at the centre-of-mass energy $\\sqrt{s} = 13$ TeV. The diagonal spin density matrix element $\\rho_{00}$ of ${\\rm D^{*+}}$ mesons was measured from the angular distribution of the"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2212.06588","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2212.06588/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"}