## Weighting Neutrinos in $f(R)$ gravity    [PDF]

Jian-hua He
In this paper, we constrain the neutrino properties in $f(R)$ gravity using the latest observations from Cosmic Microwave Background(CMB) and Baryon Acoustic Oscillation(BAO) measurements. We first constrain separately the total mass of neutrinos $\sum m_\nu$ and the effective number of neutrino species $N_{\rm eff}$ respectively. Then we constrain $N_{\rm eff}$ and $\sum m_\nu$ simultaneously. We find $\sum m_\nu<0.462 {\rm eV}$ at 95% confidence level for the combination of Planck CMB data, WMAP CMB polarization data, BAO data and high-$l$ data from Atacama Cosmology Telescope(ACT) and South Pole Telescope(SPT). We also find $N_{\rm eff}=3.32^{+0.54}_{-0.51}$ at 95% confidence level for the same data set. When constraining $N_{\rm eff}$ and $\sum m_\nu$ simultaneously, we find $N_{\rm eff}=3.58^{+0.72}_{-0.69}$ and $\sum m_\nu<0.860{\rm eV}$ at 95% confidence level respectively.
View original: http://arxiv.org/abs/1307.4876