Eur. Phys. J. C (2010) 67: 479-487
https://doi.org/10.1140/epjc/s10052-010-1317-3

Regular Article - Theoretical Physics

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

¹ Department of Physics, National Cheng-Kung University, Tainan, 701, Taiwan
² National Center for Theoretical Sciences, Hsinchu, 300, Taiwan
³ Department of Physics, National Tsing-Hua University, Hsinchu, 300, Taiwan

^* e-mail: physchen@mail.ncku.edu.tw

Received: 24 September 2009
Revised: 10 March 2010
Published online: 24 April 2010

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 , the sneutrino-mediated effects could simultaneously account for the Fermi and PAMELA data.