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Width of the 511 KeV Line from the Bulge of the Galaxy

Ariel Zhitnitsky
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Abstract

In this paper I present the detail estimations for the width of the 511 keV line produced by a mechanism when dark matter is represented by macroscopically large dense nuggets. I argue that the width of 511 keV emission in this mechanism is very narrow (in a few keV range) in agreement with all observations. The dominant mechanism of the annihilation in this case is the positronium formation e^+e^-to ^1S_0 to 2γrather than a direct e^+e^- to 2γ$ annihilation. I also discuss some generic features of the γrays spectrum (in few MeV range) resulting from this mechanism.

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Ariel Zhitnitsky. 2007-10-04. Width of the 511 KeV Line from the Bulge of the Galaxy. https://doi.org/10.1103/physrevd.76.103518

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