Galactic positrons from Z0 decay Academic Article uri icon


  • The positron excess below 10 GeV in the Galactic cosmic rays is shown to closely resemble the expected spectrum from sub-relativistic Z 0 decay. The possibility is critically examined that the Galactic dark matter is composed of neutralinos that are just above the half the Z 0 mass, and that the excess positrons derive from “decay” of virtual Z 0 bosons produced when the neutralinos annihilate. While this mechanism provides a very good fit for energies below 10 GeV, at higher energy it seems to disagree with the data given conventional assumptions about propagation.

publication date

  • January 1, 2004