Indirect detection of unstable heavy dark matter

Abstract

Unstable relics with lifetime longer than the age of the Universe could be the dark matter today. Electrons, photons and neutrinos are a natural outcome of their decay and could be searched for in cosmic rays and in $\gamma$-ray and neutrino detectors. I compare the sensitivities of these three types of searches to the mass and lifetime of a generic unstable particle. I show that if the relics constitute our galactic halo and their branching ratios into electron-positrons, photons and neutrinos are comparable, neutrino searches would probe the longest lifetimes for masses $\simge 40 \TeV$, while electron-positron searches would be better but more uncertain for lighter particles. If instead the relics are not clustered in our halo, neutrinos are more sensitive a probe than $\gamma$-rays for masses $\simge 700 \GeV$. A $ 1 \sqkm $ neutrino telescope should be able to explore lifetimes up to $\sim 10^{30}\sec$ while searching for neutrinos from unstable particles above the atmospheric background.

11pp, 1 figure available on request, PHYZZX, Uppsala U. PT17-1992

Cited by in corpus (10)

• Particle decays during the cosmic dark ages
• Extremely high energy cosmic rays from relic particle decays
• Testing the Dark Matter Scenario for PeV Neutrinos Observed in IceCube
• Constraining Very Heavy Dark Matter Using Diffuse Backgrounds of Neutrinos and Cascaded Gamma Rays
• The Concordance Cosmic Star Formation Rate: Implications from and for the Supernova Neutrino and Gamma Ray Backgrounds
• Bounds on Long-Lived Relics from Diffuse Gamma Ray Observations
• Cascade Events at IceCube+DeepCore as a Definitive Constraint on the Dark Matter Interpretation of the PAMELA and Fermi Anomalies
• Angular Correlations of the MeV Cosmic Gamma Ray Background
• Limits on R-parity violation from cosmic ray antiprotons
• Superheavy dark matter from the natural inflation in light of the highest-energy astroparticle events