Sterile neutrino fits to dark matter mass profiles in the Milky Way and in galaxy clusters

TL;DR

This paper presents evidence supporting sterile neutrinos with specific masses as dark matter candidates, fitting galaxy and cluster data, and potentially solving key cosmological problems, though further confirmation is needed.

Contribution

It provides independent evidence for sterile neutrinos with 4.0 eV and 21.4 eV masses based on dark matter distribution fits, addressing several cosmological issues.

Findings

Fits align well with galaxy and cluster observations.

Sterile neutrinos may solve the cusp and missing satellites problems.

Addresses the top-down structure formation scenario.

Abstract

In several recent papers it was claimed that SN 1987A data supports the existence of 4.0 eV and 21.4 eV active neutrino mass eigenstates, and it was shown that such large masses could be made consistent with existing constraints including neutrino oscillation data and upper limits on the neutrino flavor state masses, provided that there also exist a pair of sterile neutrino mass states whose masses are nearly degenerate with the active ones, plus a third active-sterile doublet that is tachyonic ($m^2 <0$). Here, independent evidence is presented for the existence of sterile neutrinos with the previously claimed masses based on fits to the dark matter distributions in the Milky Way galaxy and four clusters of galaxies. The fits are in excellent agreement with observations. In addition, sterile neutrinos having the suggested masses address the "cusp" problem and the missing satellites problem, as well as that of the "top down" scenario of structure formation -- previously a chief drawback of HDM particles. Nevertheless, the highly controversial nature of the claim, and the need for two free parameters in the dark matter fits, additional confirming evidence will be required before it can be considered proven.