Abstract
We study the possibility of improving the constraints on the lifetime of gravitino dark matter in scenarios with bilinear R-parity violation by estimating the amount of cosmic-ray antideuterons that can be produced in gravitino decays. Taking into account all different sources of theoretical uncertainties, we find that the margin of improvement beyond the limits already set by cosmic-ray antiproton data are quite narrow and unachievable for the next generation of experiments. However, we also identify more promising energy ranges for future experiments.
Highlights
Most current cosmic-ray detectors have the ability to determine the mass of the incoming particles – and in some cases their charge
A striking feature of figure 6 is that for masses as low as 100 GeV the gravitino decay signal can be of the same order as the astrophysical background below a few GeV, even for lifetimes as large as 1028 s, a value not yet excluded by gamma-ray and antiproton observations
When taking into account the constraints derived from antiproton observations [26], we find that the remaining parameter space for having a gravitino decay signal significantly higher than the astrophysical background becomes quite small but does not vanish completely
Summary
Most current cosmic-ray detectors have the ability to determine the mass of the incoming particles – and in some cases their charge. Even though it has been understood that because of tertiary production [18]2 and energy losses taking place during the cosmic-ray propagation [3] the difference between secondary and primary fluxes may not be as high as originally expected, antideuterons are still considered one of the most interesting species for DM searches. This interest has been extended to other yet unobserved cosmic-ray species like antihelium nuclei from DM annihilations or decays [19, 20]. In an appendix to this paper, we present some cross section parametrisations relevant for antideuteron propagation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
