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Updated: Jul 18, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Can sterile neutrinos be the dark matter?
Uros Seljak1, Alexey Makarov, Patrick McDonald
1International Center for Theoretical Physics, Trieste, Italy.
Abstract:
We use the Ly-alpha forest power spectrum measured by the Sloan Digital Sky Survey and high-resolution spectroscopy observations in combination with cosmic microwave background and galaxy clustering constraints to place limits on a sterile neutrino as a dark matter candidate in the warm dark matter scenario. Such a neutrino would be created in the early Universe through mixing with an active neutrino and would suppress structure on scales smaller than its free-streaming scale. We ran a series of high-resolution hydrodynamic simulations with varying neutrino masses to describe the effect of a sterile neutrino on the Ly-alpha forest power spectrum. We find that the mass limit is m(s) >13 keV at 95% C.L. (9 keV at 99.9%), which is above the upper limit allowed by x-ray constraints, excluding this candidate from being all of the dark matter in this model.
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