
"Cosmic-ray positrons from annihilation of weakly interacting massive particles in the galaxy"
The production of cosmic-ray positrons from the annihilation of weakly interacting massive particles (WIMP’s) is considered. Conventional supersymmetric-neutralino annihilation generally yields an unobservably small e+ flux. However, a massive WIMP (≳20 GeV) with a large annihilation cross section into a single e+e- pair produces a distinctive and observable shelf in the cosmic-ray e+ spectrum. Only Dirac neutrinos obviously generate such a feature, but it may also appear in more elaborate neutralino models. Such models are constrained by upper limits on the low-energy antiproton flux.
This actually means that there is a non-zero chance of getting one or even e few e+/e- pairs out of WIMP annihilation, not that you necessarily get pairs as El Reg's words imply:
WIMPs have their own antimatter partner particles. When matter and antimatter bits meet up, they destroy each other, in theory leaving behind, in the case of WIMPs, a pair of resultant particles: an electron and a positron (a positive electron).
I foresee:
"In a few weeks, we will be able to make an announcement"
...
"For the moment, we found nothing".
Problem, world?