Decaying Sterile Neutrinos as a Heating Source in the Milky Way Center

TL;DR

This paper proposes that decaying sterile neutrinos with masses around 16-18 keV can explain the observed two-temperature diffuse X-ray components in the Milky Way's center by providing a heating mechanism.

Contribution

It introduces a novel sterile neutrino decay model to account for the hot gas temperatures observed in the Milky Way center.

Findings

Sterile neutrinos with 16-18 keV mass can produce the observed X-ray components.

Decay of sterile neutrinos can supply sufficient energy to maintain 8 keV hot gas.

The model naturally explains the two-temperature structure of the diffuse X-ray emission.

Abstract

Recent Chandra and Newton observations indicate that there are two-temperature components ($T \sim$ 8 keV, 0.8 keV) of the diffuse x-rays emitted from deep inside the center of Milky Way. We show that this can be explained by the existence of sterile neutrinos, which decay to emit photons that can be bound-free absorbed by the isothermal hot gas particles in the center of Milky Way. This model can account for the two-temperature components naturally as well as the energy needed to maintain the $\sim$ 8 keV temperature in the hot gas. The predicted sterile neutrino mass is between 16-18 keV.