{"paper":{"title":"Discovery of Cycle-to-cycle Modulated Spectral Line Variability and Velocity Gradients in Long-period Cepheids","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.IM"],"primary_cat":"astro-ph.SR","authors_text":"Richard I. Anderson","submitted_at":"2016-08-18T19:59:58Z","abstract_excerpt":"This work reports the discovery of cycle-to-cycle modulated spectral line and atmospheric velocity gradient variability in long-period Cepheids based on 925 high-resolution optical spectra of $\\ell$ Carinae (P $\\sim$ 35.5 d) recorded during three heavy duty-cycle monitoring campaigns (in 2014, 2015, and 2016). Spectral line variability is investigated via cross-correlation functions (CCFs) computed using three sets of spectral lines (weak, solar, strong). A metallic line velocity gradient, {\\delta}v$_r$ (t), is computed as the difference between weak and strong-line RVs. CCF shape indicators B"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1608.05403","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"}