A Search for a keV Signature of Radiatively Decaying Dark Matter with Suzaku XIS Observations of the X-ray Diffuse Background

Understand

We performed the deepest search for an X-ray emission line between 0.5 and 7 keV from non-baryonic dark matter with the Suzaku XIS.

• Dark matter associated with the Milky Way galaxy was selected as the target to obtain the best signal-to-noise ratio.
• From the Suzaku archive, we selected 187 data sets of blank sky regions which were dominated by the X-ray diffuse background.
• The data sets were from 2005 to 2013.