@gpkulkarni

Model marginalized constraints on neutrino properties from cosmology

, , and . (2022)cite arxiv:2207.05167Comment: 11 pages, 3 figures, 3 tables.

Abstract

We present robust, model-marginalized limits on both the total neutrino mass ($m_\nu$) and abundance ($N_eff$) to minimize the role of parameterizations, priors and models when extracting neutrino properties from cosmology. The cosmological observations we consider are CMB temperature fluctuation and polarization measurements, Supernovae Ia luminosity distances, BAO observations and determinations of the growth rate parameter from the Data Release 16 of the Sloan Digital Sky Survey IV. The degenerate neutrino mass spectrum (which implies $m_\nu>0$) is weakly (moderately) preferred over the normal and inverted hierarchy possibilities, which imply the priors $\sum m_\nu>0.06$ and $m_\nu>0.1$ eV respectively. Concerning the underlying cosmological model, the $Łambda$CDM minimal scenario is almost always strongly preferred over the possible extensions explored here. The most constraining $95\%$ CL bound on the total neutrino mass in the $Łambda$CDM+$m_\nu$ picture is $m_\nu< 0.087$ eV. The parameter $N_eff$ is restricted to $3.080.17$ ($68\%$ CL) in the $Łambda$CDM+$N_eff$ model. These limits barely change when considering the $Łambda$CDM+$m_\nu$+$N_\rm eff$ scenario. Given the robustness and the strong constraining power of the cosmological measurements employed here, the model-marginalized posteriors obtained considering a large spectra of non-minimal cosmologies are very close to the previous bounds, obtained within the $Łambda$CDM framework in the degenerate neutrino mass spectrum. Future cosmological measurements may improve the current Bayesian evidence favouring the degenerate neutrino mass spectra, challenging therefore the consistency between cosmological neutrino mass bounds and oscillation neutrino measurements, and potentially suggesting a more complicated cosmological model and/or neutrino sector.

Description

Model marginalized constraints on neutrino properties from cosmology

Links and resources

Tags