We present cosmological constraints from a gravitational lensing mass map covering 9400 deg^{2}reconstructed from measurements of the cosmic microwave background (CMB) made by the Atacama Cosmology Telescope (ACT) from 2017 to 2021. In combination with measurements of baryon acoustic oscillations and big bang nucleosynthesis, we obtain the clustering amplitude
Improved cosmological constraints on the neutrino mass and lifetime
A bstract We present cosmological constraints on the sum of neutrino masses as a function of the neutrino lifetime, in a framework in which neutrinos decay into dark radiation after becoming nonrelativistic. We find that in this regime the cosmic microwave background (CMB), baryonic acoustic oscillations (BAO) and (uncalibrated) luminosity distance to supernovae from the Pantheon catalog constrain the sum of neutrino masses ∑ m ν to obey ∑ m ν < 0 . 42 eV at (95% C.L.). While the bound has improved significantly as compared to the limits on the same scenario from Planck 2015, it still represents a significant relaxation of the constraints as compared to the stable neutrino case. We show that most of the improvement can be traced to the more precise measurements of low ℓ polarization data in Planck 2018, which leads to tighter constraints on τ reio (and thereby on A s ), breaking the degeneracy arising from the effect of (large) neutrino masses on the amplitude of the CMB power spectrum.
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 NSFPAR ID:
 10359682
 Date Published:
 Journal Name:
 Journal of High Energy Physics
 Volume:
 2022
 Issue:
 8
 ISSN:
 10298479
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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