DarkSUSY 6.3: Freeze-in, out-of-equilibrium freeze-out, cosmic-ray
  upscattering and further new features
  DarkSUSY is a versatile tool for precision calculations of a large variety of
dark matter-related signals, ranging from predictions for the dark matter relic
density to dark matter self-interactions and rates relevant for direct and
indirect detection experiments. In all of these areas significant new code
additions have been made in recent years, since the release of DarkSUSY 6 in
2018, which we summarize in this overview. In particular, DarkSUSY now allows
users to compute the relic density for feebly interacting massive particles via
the freeze-in mechanism, but also offers new routines for freeze-out
calculations in the presence of secluded dark sectors as well as for models
where kinetic equilibrium is not fully established during the freeze-out
process. On the direct detection side, the effect of cosmic-ray upscattering of
dark matter has been fully implemented, leading to a subdominant relativistic
component in the expected dark matter flux at Earth. Finally, updated yields
relevant for indirect searches with gamma rays, neutrinos or charged cosmic
rays have been added; the new default spectra are based on a large number of
Pythia 8 runs, but users can also easily switch between various alternative
spectra. Further code details, including a manual and various concrete example
applications, are provided at www.darksusy.org.
