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arXiv · 0901.3165

Cosmic Ray Positrons from Annihilations into a New, Heavy Lepton

Abstract

Recent results from the PAMELA experiment indicate an excess in the positron spectrum above 10 GeV, but anti-proton data are consistent with the expected astrophysical backgrounds. We propose a scenario that reproduces these features. Dark matter annihilates through channels involving a new heavy vectorlike lepton which then decays by mixing with Standard Model leptons. If charged, this heavy lepton might be produced at the LHC, and could lead to multi-lepton final states or to long-lived charged tracks. Large neutrino detectors such as ANTARES or IceCube might be sensitive to a monochromatic neutrino line. This scenario may be simply embedded in various models, including an extension to the NMSSM.

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Daniel J. Phalen, Aaron Pierce, Neal Weiner. 2009-01-29. Cosmic Ray Positrons from Annihilations into a New, Heavy Lepton. https://doi.org/10.1103/physrevd.80.063513

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