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arXiv · 0906.0362

Extended MSSM Neutralinos as the Source of the PAMELA Positron Excess

Dan Hooper·Tim M. P. Tait
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Abstract

We consider a scenario within the Minimal Supersymmetric Standard Model extended by a singlet chiral superfield, in which neutralino dark matter annihilates to light singlet-like Higgs bosons, which proceed to decay to either electron-positron or muon-antimuon pairs. Unlike neutralino annihilations in the MSSM, this model can provide a good fit to the PAMELA cosmic ray positron fraction excess. Furthermore, the singlet-like scalar Higgs can induce a large Sommerfeld enhancement and provide an annihilation rate sufficient to accommodate the observed positron excess.

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Dan Hooper, Tim M. P. Tait. 2009-06-01. Extended MSSM Neutralinos as the Source of the PAMELA Positron Excess. https://doi.org/10.1103/physrevd.80.055028

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