{"paper":{"title":"Nebular H$\\alpha$ Limits for Fast Declining Type Ia Supernovae","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.HE"],"primary_cat":"astro-ph.GA","authors_text":"C. McCully, D. A. Howell, D. Hiramatsu, D. J. Sand, J. Burke, J.E. Andrews, L. Galbany, M. L. Graham, M. Lundquist, M. Moe, Nathan Smith, P. Milne, R. C. Amaro, R. Cartier, S. Valenti, S. W. Jha, S. Wyatt, T. Matheson, Y. Eweis","submitted_at":"2019-03-08T19:00:07Z","abstract_excerpt":"One clear observational prediction of the single degenerate progenitor scenario as the origin of type Ia supernovae (SNe) is the presence of relatively narrow ($\\approx$1000 km s$^{-1}$) H$\\alpha$ emission at nebular phases, although this feature is rarely seen. We present a compilation of nebular phase H$\\alpha$ limits for SN Ia in the literature and demonstrate that this heterogenous sample has been biased towards SN Ia with relatively high luminosities and slow decline rates, as parameterized by $\\Delta$m$_{15}(B)$, the difference in $B$-band magnitude between maximum light and fifteen days"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1903.03626","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"}