Preprint typeset using LATEX style emulateapj v. 2/16/10 EFFECTS OF THE NEUTRINO MASS SPLITTING ON THE NON-LINEAR MATTER POWER SPECTRUM

We have performed cosmological N-body simulations which include the effect of the masses of the individual neutrino species. The simulations were aimed at studying the effect of different neutrino hierarchies on the matter power spectrum. Compared to the linear theory predictions, we find that non-linearities enhance the effect of hierarchy on the matter power spectrum at mildly non-linear scales. The difference between the different hierarchies is about 0.5 % for a sum of neutrino masses of 0.1eV. Albeit this is a small effect, it is potentially measurable from upcoming surveys. In combina-tion with neutrinoless double-β decay experiments, this opens up the possibility of using the sky to determine if neutrinos are Majorana or Dirac fermions. Subject headings: large-scale structure of universe — neutrinos — methods: numerical 1