CALET's Sensitivity to Dark Matter Annihilation in the Galactic Halo

Abstract

CALET (Calorimetric Electron Telescope), installed on the ISS in August 2015, directly measures the electron+positron cosmic rays flux up to 20 TeV. With its proton rejection capability of 1:10^5 and an aperture of 1200 cm^2 sr, it will provide good statistics even well above one TeV, while also featuring an energy resolution of 2%, which allows it to detect fine structures in the spectrum. Such structures may originate from Dark Matter annihilation or decay, making indirect Dark Matter search one of CALET's main science objectives among others such as identification of signatures from nearby supernova remnants, study of the heavy nuclei spectra and gamma astronomy. The latest results from AMS-02 on positron fraction and total electron+positron flux can be fitted with a parametrization including a single pulsar as an extra power law source with exponential cut-off, which emits an equal amount of electrons and positrons. This single pulsar scenario for the positron excess is extrapolated into the TeV region and the expected CALET data for this case are simulated. Based on this prediction for CALET data, the sensitivity of CALET to Dark Matter annihilation in the galactic halo has been calculated. It is shown that CALET could significantly improve the limits compared to current data, especially for those Dark Matter candidates that feature a large fraction of annihilation directly into electron+positron, such as the LKP (Lightest Kaluza-Klein Particle).

13 pages, 8 figures

References in corpus (5)

• Observation of an anomalous positron abundance in the cosmic radiation
• The ATNF Pulsar Catalogue
• Constraints on Dark Matter Annihilation in Clusters of Galaxies with the Fermi Large Area Telescope
• Pulsars versus Dark Matter Interpretation of ATIC/PAMELA
• Low energy cosmic ray positron fraction explained by charge-sign dependent solar modulation

Cited by in corpus (5)

• Energy Calibration of CALET Onboard the International Space Station
• Dependence of accessible dark matter annihilation cross-sections on the density profiles of dwarf spheroidal galaxies with the Cherenkov Telescope Array
• Cosmic-Ray Signatures of Dark Matter from a Flavor Dependent Gauge Symmetry Model with Neutrino Mass Mechanism
• Decaying Fermionic Dark Matter Search with CALET
• An Interpretation of the Cosmic Ray $e^{+}+e^{-}$ Spectrum from 10 GeV to 3 TeV Measured by CALET on the ISS