On the 511 keV emission line of positron annihilation in the Milky Way

Abstract

I review our current understanding of positron sources in the Galaxy, on the basis of the reported properties of the observed 511 keV annihilation line. It is argued here that most of the disk positrons propagate away from the disk and the resulting low surface brightness annihilation emission is currently undetectable by SPI/INTEGRAL. It is also argued that a large fraction of the disk positrons may be transported via the regular magnetic field of the Galaxy into the bulge and annihilate there. These ideas may alleviate current difficulties in interepreting INTEGRAL results in a "conventional" framework.

arXiv comment7 pages, 2 figures, paper presented in "Astronomy with Radioactivities" (Ringberg, Germany, january 2008), to appear in New Astronomy Reviews

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Cited by in corpus (6)

• The 511 keV emission from positron annihilation in the Galaxy
• Gamma-ray spectroscopy of Positron Annihilation in the Milky Way
• The normal Type Ia SN 2003hv out to very late phases
• A new twist on excited dark matter: implications for INTEGRAL, PAMELA/ATIC/PPB-BETS, DAMA
• Metastable dark matter mechanisms for INTEGRAL 511 keV $\gamma$ rays and DAMA/CoGeNT events
• Exciting dark matter in the galactic center