Toward the full test of the nuMSM sterile neutrino dark matter model with Athena

TL;DR

This paper evaluates Athena's X-IFU instrument's capability to detect keV-scale sterile neutrino dark matter decay signals, aiming to fully test the nuMSM model through spectral line searches in dwarf galaxies.

Contribution

It demonstrates that Athena's X-IFU can significantly improve sensitivity to sterile neutrino decay signals, enabling a comprehensive test of the nuMSM dark matter model.

Findings

X-IFU's high energy resolution enhances detection sensitivity.

Full parameter space coverage of nuMSM sterile neutrino masses and mixing angles.

Potential to confirm or exclude the nuMSM dark matter candidate.

Abstract

We discuss the potential of Athena X-ray telescope, in particular of its X-ray Integral Field Unit (X-IFU), for detection of the signal from the light-weight decaying dark matter with mass in the keV range. We show that high energy resolution and large collection area of X-IFU will provide an improvement of sensitivity which will be sufficient for the full test of the neutrino Minimal extension of the Standard Model (nuMSM). Search for the narrow spectral line produced by the decay of the dark matter sterile neutrino in the spectra of dwarf spheroidal galaxies with X-IFU will explore the whole allowed range masses and mixing angles of the nuMSM lightest sterile neutrino and in this way either to find the dark matter signal or rule out the nuMSM model.