Positron annihilation radiation from the Galactic center regionObservations show that there are two components of positron annihilation radiation from the region of the Galactic center: a variable component resulting from one or just a few compact sources at or near the Galactic center and a steady, diffuse component resulting from positron annihilation in the Galactic disk. The diffuse component is modeled using the observed longitude distributions of 70-150 MeV gamma rays, CO, and hot plasma revealed by Fe line emission. Recent results on positron annihilation in the interstellar medium are reviewed and the implications of the annihilation processes on the fraction of positrons annihilating via positronium and on the shape of the 511 keV annihilation line are discussed. The sources of diffuse Galactic positrons are also reviewed and the nature of the compact source of annihilation radiation near the Galactic center is discussed.
Document ID
19920061004
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Ramaty, R. (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Lingenfelter, R. E. (California, University La Jolla, United States)
Date Acquired
August 15, 2013
Publication Date
January 1, 1991
Subject Category
Astrophysics
Meeting Information
Meeting: International Symposium on Gamma-Ray Line Astrophysics