The explosion was fairly faint for a Type-IIb supernova with its peak
absolute magnitude being −16.5 ± 0.1 mag. It was also a relatively hydrogen rich supernova for its type. Currently, SN 2024abfo is the least luminous SN IIb with direct progenitor detections.
Spectra The early spectra of SN 2024abfo was dominated by
Balmer lines that have broad
P Cygni profiles. This shows that the ejecta produced was traveling at a velocity of 22,500 km/s. Around a month after the explosion, spectra show that it was going through a transition towards being
helium-dominated with the hydrogen lines not completely disappearing. Its fading was slow and linear, lasting for around 2 months. Similar to
SN 2008ax, it does not show a prominent double-peaked light curve.
Progenitor Single star models of the progenitor of SN 2024abfo show that the progenitor likely would have been a hot
yellow supergiant star with a mass of around 11-15 solar masses. The most probable model for the progenitor of the supernova is the binary model. This model predicts that the progenitor was a 12 solar mass star in a binary system with a 1.2 solar mass companion. They would have had an orbital period of around 1.73 years. == References ==