A halo-independent lower bound on the dark matter capture rate in the Sun from a direct detection signal

Understand

We show that a positive signal in a dark matter (DM) direct detection experiment can be used to place a lower bound on the DM capture rate in the Sun, independent of the DM halo.

• For a given particle physics model and DM mass we obtain a lower bound on the capture rate independent of the local DM density, velocity distribution, galactic escape velocity, as well as the scattering cross section.
• We illustrate this lower bound on the capture rate by assuming that upcoming direct detection experiments will soon obtain a significant signal.
• When comparing the lower bound on the capture rate with limits on the high-energy neutrino flux from the Sun from neutrino telescopes, we can place upper limits on the branching fraction of DM annihilation channels leading to neutrinos.