Abstract Details
| Name: Anjasha Gangopadhyay Affiliation: Oskar Klein Centre, Stockholm University, Sweden Conference ID: ASI2025_414 Title : A thourough investigation on the evolution of Helium rich interacting (Ibn) supernovae Authors and Co-Authors : Anjasha Gangopadhyay, Kuntal Misra, Jesper Sollerman, Mridweeka Singh, Raya Dastidar Abstract Type : Oral Abstract Category : High Energy Phenomena, Fundamental Physics and Astronomy Abstract : Type Ibn supernovae (SNe), a rare subclass of core-collapse explosions, are characterized by unique circumstellar interactions with helium-rich material, producing distinct narrow emission lines. This work presents the studies on two Ibn SN 2019uo; SN 2019wep, and a compiled analysis of a sample of SNe Ibn observed by Zwicky Transient Factory (ZTF) from 2018 - 2024. This provide valuable insights into the nature and diversity within this SN type, revealing variations in progenitor properties, mass-loss history, and CSM interaction. SN 2019uo and SN 2019wep highlight differences in luminosity decline rates (typically around 0.1 mag/day for 30 days) and circumstellar medium (CSM) density, suggesting distinct progenitor characteristics. The compiled sample from the ZTF broadens this perspective by comparing Type Ibn SNe with other interacting supernovae, emphasizing the role of CSM properties in shaping observable features and expanding our understanding of SN explosions in helium-rich environments. We typically infer that the lightcurves are mostly fast risers and decliners with some exceptions. The lightcurves are mostly driven by CSM interaction rather than radioactive decay. Spectroscopically, they show both emission and P-cygni He lines due to different CSM densities and structures. The line strengths hint towards Wolf-Rayet as typical progenitors. The unique CSM interactions and mass-loss rate estimates in Type Ibn SNe offer clues to episodic mass loss before explosion, enhancing our knowledge of core-collapse mechanisms. Continued observation of Type Ibn events is essential to further explore the progenitor diversity and mass-loss dynamics underlying these explosive phenomena. |