Model-independent mass limits assess the robustness of current cosmological measurements of the neutrino mass scale. Consistency between high-multipole and low-multiple cosmic microwave background observations measuring such scale further valuates the constraining power of present data. We derive here up-to-date limits on neutrino masses and abundances exploiting either the Data Release 4 of the Atacama Cosmology Telescope (ACT) or the South Pole Telescope polarization measurements from SPT-3G, envisaging different nonminimal background cosmologies and marginalizing over them. By combining these high-$\ell$ observations with supernova Ia, baryon acoustic oscillations (BAO), redshift space distortions (RSD) and a prior on the reionization optical depth from WMAP data, we find that the marginalized bounds are competitive with those from Planck analyses. We obtain $\sum m_{\nu }<0.139\mathrm{eV}$ and $N_{\mathrm{eff}}=2.82\pm 0.25$ in a dark energy quintessence scenario, both at 95% CL. These limits translate into $\sum m_{\nu }<0.20\mathrm{eV}$ and $N_{\mathrm{eff}}=2.79_{-0.28}^{+0.30}$ after marginalizing over a plethora of well-motivated fiducial models. Our findings reassess both the strength and the reliability of cosmological neutrino mass constraints.

• Received 6 June 2023
• Accepted 15 September 2023

DOI:https://doi.org/10.1103/PhysRevD.108.083509