–
 •
 •Example:
 Like White Dwarf accretion disk but w/ black hole instead
 –Gas
 from red giant companion spills over towards black hole
 –Gas
 spirals in toward black hole, through accretion disk
 •Gas
 will be much hotter because it falls further, to very small RS
 –Gas
 will be moving at very high velocity
 •Much
 faster than with white dwarf since much closer  (P2 µ a3)
 •
 •Signature
 of black hole:  Very high energy
 release, very high
 velocity
 –
 •We find MASSIVE black holes in centers of most
 galaxies