A New Solar System Dark Matter Population of Weakly Interacting Massive Particles

Perturbations due to the planets combined with the non-Coulomb nature of the gravitational potential in the Sun imply that weakly interacting massive particles (WIMPs) that are gravitationally captured by scattering in surface layers of the Sun can evolve into orbits that no longer intersect the Sun. For orbits with a semimajor axis < 1/2 of Jupiter close-quote s orbit, such WIMPs can persist in the solar system for > 109 years, leading to a previously unanticipated population intersecting Earth close-quote s orbit. For WIMPs detectable in the next generation of detectors, this population can provide a complementary signal, in the keV range, to that of galactic halo dark matter. copyright 1998 The American Physical Society