http://arxiv.org/abs/2201.01888
The Cosmic Neutrino Background (C$\nu$B) anisotropies for massive neutrinos are a unique probe of large-scale structure formation. The redshift-distance measure is completely different for massive neutrinos as compared to electromagnetic radiation. The C$\nu$B anisotropies in massive neutrinos grow in response to non-relativistic motion in gravitational potentials seeded by relatively high $k$-modes. Differences in the early phases of large-scale structure formation in Warm Dark Matter (WDM) versus Cold Dark Matter (CDM) cosmologies have an impact on the magnitude of the C$\nu$B anisotropies for contributions to the angular power spectrum that peak at high $k$-modes. We take the example of WDM consisting of 2 keV sterile neutrinos and show that the C$\nu$B anisotropies for 0.05 eV neutrinos drop off at high-$l$ multipole moment in the angular power spectrum relative to CDM. At the same angular scales that one can observe baryonic acoustical oscillations in the CMB, the C$\nu$B anisotropies begin to become sensitive to differences in WDM and CDM cosmologies. The precision measurement of high-$l$ multipoles in the C$\nu$B neutrino sky map is a potential possibility for the PTOLEMY experiment with thin film targets of spin-polarized atomic tritium superfluid that exhibit significant quantum liquid amplification for non-relativistic relic neutrino capture.
C. Tully and G. Zhang
Fri, 7 Jan 22
18/34
Comments: N/A