2009/04/30 by R. E. Lingenfelter, J. C. Higdon, R. E. Rothschild · 1 citation
Physics and Astronomy · #astro-ph.HE
paper · pdf · doi:10.1103/physrevlett.103.031301
published as Phys.Rev.Lett.103:031301,2009 · 4 pages, no figures, 85 references, revised version accepted for publication in Physical Review Letters
arxiv created 2009/06/15 · arxiv updated 2009/12/01
Assuming Galactic positrons do not go far before annhilating, a difference between the observed 511 keV annihilation flux distribution and that of positron production, expected from beta-plus decay in Galactic iron nucleosynthesis, was evoked as evidence of a new source and a signal of dark matter. We show, however, that the dark mater sources can not account for the observed positronium fraction without extensive propagation. Yet with such propagation, standard nucleosynthetic sources can fully account for the spatial differences and the positronium fraction, leaving no signal for dark mater to explain.