{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/velocity-evolution-of-broad-line-ic","title":"Velocity evolution of broad-line Ic supernovae with and without gamma-ray bursts","arxiv_id":"2411.11503","date":"2024-11-18","proceeding":null,"authors":["Gabriel Finneran","Laura Cotter","Antonio Martin-Carrillo"],"abstract":"More than 60 broad-lined type Ic (Ic-BL) supernovae (SNe) are associated with a long gamma-ray burst (GRB). However, many type Ic-BL SNe exhibit no sign of an associated GRB. On average, the expansion velocities of GRB-associated type Ic-BL SNe (GRB-SNe) are greater than those of type Ic-BL SNe without an associated GRB. This work presents the largest spectroscopic sample of type Ic-BL SNe with and without GRBs to date, consisting of 61 ordinary type Ic-BL SNe and 13 GRB-SNe. The goal of this work is to compare the evolution of SN expansion velocities in cases where an ultra-relativistic jet has been launched (GRB-SNe) and cases where no GRB jet is inferred from observations (ordinary type Ic-BL SNe), to search for possible jet influences. To do this we measured the expansion velocities of the Fe II and Si II features observed in the spectra of type Ic-BL SNe using a spline fitting method and fitted the velocity evolution with single and broken power-laws. In each analysis we compared two populations: ordinary type Ic-BL SNe and GRB-SNe. We find that the expansion velocities of the Fe II and Si II features are similar between these populations, in contrast with previous studies. The Fe II and Si II power-law indices indicate that GRB-SNe decline at similar rates to ordinary type Ic-BL supernovae. Broken power-law evolution appears to be more common for the Si II feature. This observation may hint at a two-component ejecta model, such as a GRB jet or a cocoon. Neither the velocities nor their evolution can be used to distinguish between ordinary type Ic-BL SNe and GRB-SNe. Velocities consistent with broken power-law evolution may indicate the presence of a GRB jet in some of these ordinary type Ic-BL SNe, but this is likely not as robust as late-time radio surveys. These results suggest that GRB-SNe and ordinary type Ic-BL SNe are drawn from the same underlying population of events.","url_abs":"https://arxiv.org/abs/2411.11503v1","url_pdf":"https://arxiv.org/pdf/2411.11503v1.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"velocity-evolution-of-broad-line-ic","repo_url":"https://github.com/gabrielf98/emlineclipper","is_official":1,"mentioned_in_paper":1,"mentioned_in_github":1,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"syntology_url":null,"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}