Resolving Fermi, PAMELA and ATIC anomalies in split supersymmetry without R-parity

Abstract

A long-lived decaying dark matter as a resolution to Fermi, PAMELA and ATIC anomalies is investigated in the framework of split supersymmetry (SUSY) without R-parity, where the neutralino is regarded as the dark matter and the extreme fine-tuned couplings for the long-lived neutralino are naturally evaded in the usual approach. The energy spectra of electron and positron are from not only the direct neutralino decays denoted by χ → e+e-ν, but also the decaying chains such as. We find that with a proper lifetime of the neutralino, slepton-mediated effects could explain the ATIC and PAMELA data well, but an inconsistence occurs to the Fermi and PAMELA data without considering the ATIC one. However, by a suitable combination of χ → e+e-ν and χ → e+νμ(→ νμeν̄e, the sneutrino-mediated effects could simultaneously account for the Fermi and PAMELA data. © 2010 Springer-Verlag / Societ̀ Italiana di Fisica.