Lecture 34

Gamma-Ray Bursts: Central Engine Physics

• long-soft bursts
  • hypernovae
  • collapsars
• short-hard bursts:
  • compact object mergers--neutron stars, black holes; movie: Illinois relativity group
  • collapsars; movie: Illinois relativity group

Type Ia Supernovae

Type Ia Supernovae Observed

• SN 1994D
  SNIa light curve movie
• Type Ia SNe as standardizable candles
  raw and cooked light curves

Type Ia Supernova Physics

• white dwarf accretion
• thermonuclear explosion
• nucleosynthesis: iron peak
• models U Chicago 3-D simulation

Type Ia Supernova: Open Questions

• who is the progenitor? single- vs double-degenerate
• detonation--deflagration transition?
• origin of lightcurve universality, diversity?
• environmental/evolutionary effects on lightcurve standardization?

Supernova Nucleosynthesis: Evolution Effects

• timescale for core-collapse, thermonuclear explosions
• encodeing in solar abundances
• comparison with halo star abundances