2009/06/30 by Wilfried Buchmüller, Alejandro Ibarra, Tetsuo Shindou +2 · 1 citation
Physics and Astronomy · #Antiproton #Cosmology #Dark Matter and Cosmic Phenomena #Dark matter #Fermi Gamma-ray Space Telescope #Flux (metallurgy) #Gravitino #High-Energy Particle Collisions Research #Leptogenesis #Positron #Pulsars and Gravitational Waves Research #astro-ph.CO #hep-ph #hep-th
paper · pdf · doi:10.1088/1475-7516/2009/09/021
published as JCAP 0909:021, 2009 · 21 pages, 6 figures. v3: published version
arxiv created 2009/08/31 · openalex publication_date 2009/09/15 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
We analyse the cosmic-ray signatures of decaying gravitino dark matter in a model-independent way based on an operator analysis. Thermal leptogenesis and universal boundary conditions at the GUT scale restrict the gravitino mass to be below 600 GeV. Electron and positron fluxes from gravitino decays, together with the standard GALPROP background, cannot explain both the PAMELA positron fraction and the electron + positron flux recently measured by Fermi LAT. For gravitino dark matter, the observed fluxes require astrophysical sources. The measured antiproton flux allows for a sizable contribution of decaying gravitinos to the gamma-ray spectrum, in particular a line at an energy below 300 GeV. Future measurements of the gamma-ray flux will provide important constraints on possible signatures of decaying gravitino dark matter at the LHC.