© Charles Chandler

 

Type I No hydrogen	Type Ia Presents a singly ionized silicon (Si II) line at 615.0 nm (nanometers), near peak light				Thermal runaway
	Type Ib/c Weak or no silicon absorption feature	Type Ib Shows a non-ionized helium (He I) line at 587.6 nm			Core collapse
		Type Ic Weak or no helium
Type II Shows hydrogen	Type II-P/L/N Type II spectrum throughout	Type II-P/L No narrow lines		Type II-P Reaches a "plateau" in its light curve
				Type II-L Displays a "linear" decrease in its light curve (linear in magnitude versus time).1
		Type IIn Some narrow lines
	Type IIb Spectrum changes to become like Type Ib