A global look into the world of interacting supernovae

TL;DR

This paper provides a comprehensive analysis of interacting supernovae types IIn and Ibn, revealing their heterogeneity, spectral diversity, and the nature of their circumstellar environments through detailed temporal and spectroscopic observations.

Contribution

It offers the first detailed comparative study of SNe IIn and Ibn, highlighting their differences in brightness, duration, and spectral features, and models their circumstellar interactions.

Findings

SNe IIn are heterogeneous with multi-staged evolution.

SNe Ibn are more homogeneous, fainter, and short-lived.

Spectral diversity in Hα and He profiles indicates complex CSM interactions.

Abstract

Interacting supernovae (SNe) IIn and Ibn show narrow emission lines and have always been a mysterious and unsolved genre in SNe physics. We present a comprehensive analysis of the temporal and spectroscopic behaviour of a group of interacting SNe~IIn and Ibn. We choose SNe~2012ab, 2020cui, 2020rc and 2019uo as representative members of these SN sub-types to probe the nature of explosion. Our study reveals that SNe~IIn are heterogeneous, bright depicting multi-staged temporal evolution while SNe~Ibn are moreover homogeneous, comparatively fainter than SNe~IIn and short lived, but limited in sample to firmly constrain the homogeneity. The spectroscopic features display a great diversity in H$\alpha$ and He profiles for both SNe~IIn and Ibn. The representative SN~Ibn also show flash ionisation signatures of CIII and NIII. Modelling of H$\alpha$ reveals that SNe~IIn have in general an asymmetric CSM which interacts with SN ejecta resulting in diversity in H$\alpha$ profiles.