What are the differences between supernova types 1a, 1b, 1c and 2?

Type I is associated with binary star systems and has no hydrogen lines.

Type Ia has strong silicon lines at maximum light.

Type Ib has no silicon lines at maximum light and is about 1 - 2 magnitudes fainter than Ia's. helium lines are present and probably due to helium detonation on a carbon-oxygen core.

Type Ic have no helium lines and also no silicon lines at maximum light.

Type II is associated with individual massive stars and has hydrogen lines due to the overlying stellar atmosphere.


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