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arXiv · 0711.3008

The Galactic Positron Annihilation Radiation & The Propagation of Positrons in the Interstellar Medium

J. C. Higdon·R. E. Lingenfelter·R. E. Rothschild
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Abstract

We consider positron propagation in the interstellar medium and show that the positrons from the beta-plus decay chains of the radioactive nuclei Ni-56, Ti-44, and Al-26, produced in Galactic supernovae, can fully account for all the features of the diffuse Galactic 511 keV annihilation radiation observed by INTEGRAL/SPI. We also predict additional measurable features that can further test the origin of positrons and provide new information on the nature of the interstellar medium.

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J. C. Higdon, R. E. Lingenfelter, R. E. Rothschild. 2009-04-06. The Galactic Positron Annihilation Radiation & The Propagation of Positrons in the Interstellar Medium. https://doi.org/10.1088/0004-637x%2F698%2F1%2F350

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