Positron Astrophysics at the Galactic Center: Observations and Simulations
11 February 1987
A series of balloon and satellite measurements dating back to 1970 have established the existence of a powerful, compact and variable source of electron-positron annihilation line (511 keV) radiation at the center of the Milky Way. These observations are reviewed along with a laboratory simulation experiment aimed at understanding the annihilation medium.