Detectability of a subdominant density component of cold dark matter

Here we examine the delectability of collisionless dark matter candidates that may constitute not all but only a subdominant component of galactic cold dark matter. We show that direct WIMP searches would not be severely affected by the reduced density. In fact, the direct detection rates of neutralinos stay almost constant even if neutralinos constitute 1% of the halo dark matter. Only for lower densities do the rates decrease with density. Even neutralinos accounting for only 10(-4) of the local dark halo density are within proposed future discovery limits. We comment also on axions and indirect WIMP searches. (C) 2002 Elsevier Science B.V. All rights reserved.