Theory suggests that stars with initial masses greater than 25–30 solar masses end up as Wolf-Rayet stars, which are deficient in hydrogen in their outer layers; subsequent supernova explosions should produce ejecta of low kinetic energy, a faint optical luminosity and a small mass fraction of radioactive nickel, but no weak, hydrogen-deficient, core-collapse supernovae have hitherto been see. Now, SN 2008ha is reported to be a faint hydrogen-poor supernova.
- S. Valenti
- A. Pastorello
- S. J. Smartt