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arXiv · astro-ph/0608017

Revised WMAP constraints on neutrino masses and other extensions of the minimal $Λ$CDM model

Abstract

Recently, two issues concerning the three-year WMAP likelihood code were pointed out. On large angular scales ($l \lesssim 30$), a sub-optimal likelihood approximation resulted in a small power excess. On small angular scales ($l \gtrsim 300$), over-subtraction of unresolved point sources produced a small power deficit. For a minimal six-parameter cosmological model, these two effects conspired to decrease the value of $n_s$ by $\sim 0.7 σ$. In this paper, we study the change in preferred parameter ranges for more extensive cosmological models, including running of $n_s$, massive neutrinos, curvature, and the equation of state for dark energy. We also include large-scale structure and supernova data in our analysis. We find that the parameter ranges for $α_s$, $Ω_k$ and $w$ are not much altered by the modified analysis. For massive neutrinos the upper limit on the sum of the neutrino masses decreases from $M_ν< 1.90$eV to $M_ν< 1.57$eV when using the modified WMAP code and WMAP data only. We also find that the shift of $n_s$ to higher values is quite robust to these extensions of the minimal cosmological model.

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BibTeXRIS

Jostein R. Kristiansen, Hans Kristian Eriksen, Oystein Elgaroy. 2006-12-19. Revised WMAP constraints on neutrino masses and other extensions of the minimal $Λ$CDM model. https://doi.org/10.1103/physrevd.74.123005

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