The astrophysical dark matter can't decay on any reasonably short timescale (since it's still here!) If there is only one DM particle and it's a Majorana (i.e.

The astrophysical dark matter can't decay on any reasonably short timescale (since it's still here!) If there is only one DM particle and it's a Majorana (i.e. its own antiparticle), then they can annihilate and produce all sorts of things, which is why experiments like AMS-2, Fermi, and IceCube are looking for annihilation products (the keyword is "indirect dark matter detection").