Relic Neutrinos, thermal axions and cosmology in early 2014
  We present up to date cosmological bounds on the sum of active neutrino
masses as well as on extended cosmological scenarios with additional thermal
relics, as thermal axions or sterile neutrino species. Our analyses consider
all the current available cosmological data in the beginning of year 2014,
including the very recent and most precise Baryon Acoustic Oscillation (BAO)
measurements from the Baryon Oscillation Spectroscopic Survey. In the minimal
three active neutrino scenario, we find Sum m_nu < 0.22 eV at 95% CL from the
combination of CMB, BAO and Hubble Space Telescope measurements of the Hubble
constant. A non zero value for the sum of the three active neutrino masses of
about 0.3 eV is significantly favoured at more than 3 standard deviations when
adding the constraints on sigma_8 and Omega_m from the Planck Cluster catalog
on galaxy number counts. This preference for non zero thermal relic masses
disappears almost completely in both the thermal axion and massive sterile
neutrino schemes. Extra light species contribute to the effective number of
relativistic degrees of freedom, parameterised via Neff. We found that when the
recent detection of B mode polarization from the BICEP2 experiment is
considered, an analysis of the combined CMB data in the framework of LCDM+r
models gives Neff=4.00pm0.41, suggesting the presence of an extra relativistic
relic at more than 95 % c.l. from CMB-only data.
