In this review, I discuss the suitability of massive star progenitors, evolved in isolation or in interacting binaries, for the production of observed supernovae (SNe) IIb, Ib, Ic. These SN types can be explained through variations in composition. The critical need of non-thermal effects to produce He I lines favours low-mass He-rich ejecta (in which ^56 Ni can be more easily mixed with He) for the production of SNe IIb/Ib, which thus may arise preferentially from moderate-mass donors in interacting binaries. SNe Ic may instead arise from higher mass progenitors, He-poor or not, because their larger CO cores prevent efficient non-thermal excitation of He i lines. However, current single star evolution models tend to produce Wolf-Rayet (WR) stars at death that have a final mass of > 10 M☉. Single WR star explosion models produce ejecta that are too massive to match the observed light curve widths and rise times of SNe IIb/Ib/Ic, unless their kinetic energy is systematically and far greater than the canonical value of 10^56 erg. Future work is needed to evaluate the energy/mass degeneracy in light curve properties. Alternatively, a greater mass loss during the WR phase, perhaps in the form of eruptions, as evidenced in SNe Ibn, may reduce the final WR mass. If viable, such explosions would nonetheless favour a SN Ic, not a Ib.
Wolf-Rayet Stars: Proceedings of an International Workshop held in Potsdam
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