Enhanced Dark Matter Annihilation Rate for Positron and Electron Excesses from Q-ball Decay

TL;DR

This paper proposes that Q-ball decay within Affleck-Dine baryogenesis models can explain dark matter and cosmic ray excesses by requiring an enhanced annihilation cross-section, aligning with observations from PAMELA, ATIC, and PPB-BETS.

Contribution

It demonstrates that Q-ball decay can produce dark matter with an increased annihilation rate, providing a unified explanation for cosmic ray excesses and dark matter abundance.

Findings

Q-ball decay can produce the correct dark matter density with enhanced annihilation.

Reheating temperature is around 30 GeV, decay temperature 10-100 MeV.

Annihilation cross-section needs to be ~10^3 times the thermal relic value.

Abstract

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 10-100 MeV. The LSPs produced by Q-ball decay annihilate down to the observed dark matter density if the cross-section is enhanced by a factor ~ 10^3 relative to the thermal relic cross-section.