Following the discovery and classification of SN 2021yfj whose unique early spectra are completely dominated by prominent emission lines of highly ionized silicon, sulphur and argon, lacking prominent features from carbon, oxygen, helium and hydrogen, we propose to tentatively introduce a new...
ui.adsabs.harvard.edu
Found the paper - took a second. A surface-level look reveals this is a supernova dominated in its spectra by argon, sulfur, and ionized silicon. The funkiest part is that it lacks the typical type I/II supernova spectrum containing strong hydrogen, carbon, helium, oxygen, etc.
Definitely very odd and interesting indeed! It suggests that the inner layers of the progenitor star are being expelled, at the very least,
before the outer layers are, which is super odd and we have no idea what that could entail. There’s probably some incredibly violent and unknown mass loss mechanism occurring here according to this paper:
Observations of SN 2021yfj reveal that its progenitor is a massive star stripped down to its O/Si/S core, which remarkably continued to expel vast quantities of silicon-, sulfur-, and argon-rich material before the explosion, informing us that current theories for how stars evolve are too narrow.
www.nature.com
I will say though, there’s not a lot I can interact with here outside of just the reporting of this odd observation. I can’t seem to find a full pdf for the first paper I listed in this post. When I get to my computer, I’ll take a closer look.
EDIT: I wouldn’t be surprised in the slightest if such a supernova involved a Wolf-Rayet star of some kind (I can explain what these are in a separate post, but tldr for now) but it would likely have to require a new type of WR star, if that’s the case. This is pure conjecture by me, and shouldn’t be taken as the truth, however.
