The nature of supernovae

 

Baade & Zwicky 1934 [1]
  Energy release ergs
  Remnant could be a neutron star
  Cosmic rays may form in supernovae
  Expanding shells of gas km/s

Type I
  Heavy element lines
  From population II stars (low metalicity)
  Occur in elliptical and spiral galaxies
  1a - Merger or collapse of white dwarfs
  1b - Carbon flash destroys star

Type II
  Predominantly H lines
  From population I stars (high metalicity)
  Occur only in spiral galaxies
  Core collapse in massive stars