ASASSN-15hy: An Underluminous, Red 03fg-like Type Ia Supernova
Lu et al. (2021) · ApJ 920, 107
ASASSN-15hy belongs to the peculiar "super-Chandrasekhar" 03fg-like subclass of Type Ia supernovae, yet is unusually underluminous and red compared to its groupmates. Optical and near-infrared observations reveal broad light curves, persistent carbon features, and a low silicon velocity. These properties are best explained by a "deflagration core-degenerate" scenario, the secular merger of a white dwarf with the degenerate core of an asymptotic giant branch star, requiring a low-metallicity progenitor.
Read paper →