The Diverse Properties of Type Icn Supernovae Point to Multiple Progenitor Channels

Understand

We present a sample of Type Icn supernovae (SNe Icn), a newly-discovered class of transients characterized by their interaction with H- and He-poor circumstellar material (CSM).

• This sample is the largest collection of SNe Icn to date and includes observations of two published objects (SN 2019hgp and SN 2021csp) as well as two objects (SN 2019jc and SN 2021ckj) not yet published in the literature.
• The SNe Icn display a range of peak luminosities, rise times, and decline rates, as well as diverse late-time spectral features.
• To investigate their explosion and progenitor properties we fit their bolometric light curves to a semi-analytical model consisting of luminosity inputs from circumstellar interaction and radioactive decay of $^{56}$Ni.