Improved cosmological constraints on the neutrino mass and lifetime

Autor: Abellán, Guillermo F., Chacko, Zackaria, Dev, Abhish, Du, Peizhi, Poulin, Vivian, Tsai, Yuhsin
Rok vydání: 2021
Předmět:
Zdroj: JHEP 08, 076 (2022)
Druh dokumentu: Working Paper
DOI: 10.1007/JHEP08(2022)076
Popis: 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 non-relativistic. 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 $\sum m_\nu$ to obey $\sum m_\nu< 0.42$ eV at (95$\%$ C.L.). While the 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-$\ell$ polarization data in Planck 2018, which leads to tighter constraints on $\tau_{\rm reio}$ (and thereby on $A_s$), breaking the degeneracy arising from the effect of (large) neutrino masses on the amplitude of the CMB power spectrum.
Comment: 24 pages, 8 figures. v2 matches published JHEP version. Comments welcome!
Databáze: arXiv