Enhanced dark matter annihilation rate for positron and electron excesses from Q-ball decay.
We show that Q-ball decay in Affleck-Dine baryogenesis models can account for dark matter when the annihilation cross section is sufficiently enhanced to explain the positron and electron excesses observed by PAMELA, ATIC, and PPB-BETS. For Affleck-Dine baryogenesis along a d=6 flat direction, the reheating temperature is approximately 30 GeV and the Q-ball decay temperature is in the range of 10-100 MeV. The lightest supersymmetric particles produced by Q-ball decay annihilate down to the observed dark matter density if the cross section is enhanced by a factor approximately 10(3) relative to the thermal relic cross section.
McDonald
John
J
Cosmology and Astroparticle Physics Group, University of Lancaster, Lancaster LA1 4YB, United Kingdom. j.mcdonald@lancaster.ac.uk