Date of Award

12-2008

Document Type

Thesis

Degree Name

Master of Science (MS)

Legacy Department

Physics

Advisor

Lesing, Mark

Committee Member

Hartmann , Dieter

Committee Member

King , Jeremy

Abstract

The 511 keV positron annhilation emission from the Galactic bulge has yet to solely be attributed to any astrophysical source of positrons. The 511 keV line, characteristic of electron-positron annihilation, was discovered in 1970 by Johnson and Haymes [1973] almost 40 years ago. Most recently the INTERnational Gamma-Ray Astrophysical Laboratory (INTEGRAL) [Knodlseder 1997] has measured the annihilation rates of both components of the Galaxy. The bulge and disk annihilation rates are (1.5 ± 0.1) x 10^43 e+ s^-1 and(0.3 ± 0.2) x 10^43 e+ s^-1, respectively. The ratio of the bulge rate to that of the disk ranges from 3-9. Many astrophysical galactic sources have been proposed to be the source of positrons.

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