“This newly proposed dark matter candidate would not only be lighter than existing hypothetical suspects, but it would also be self-annihilating. This means that when two particles of dark matter meet, they destroy each other and create a negatively charged electron and its positively charged equivalent, a positron.

This process and the flood of electrons and positrons would provide the energy needed to strip electrons away from neutral atoms, a process called ionization, in dense gas in the center of the Milky Way. That could explain why there is so much ionized gas in the central region called the Central Molecular Zone (CMZ).”