Within the minimal supergravity model (mSUGRA) framework, the expectation for the relic density of neutralinos exceeds the WMAP determination, unless neutralinos (a) have a significant Higgsino component, (b) have a mass close to half that of a heavy Higgs boson, or (c) can efficiently coannihilate with a charged or colored particle. Within a one-parameter extension of the mSUGRA model which includes nonuniversal Higgs masses, we show that agreement with the WMAP data can be obtained over a wide range of mSUGRA parameters for scenarios (a) and (b), so that the phenomenological implications may be much more diverse than in mSUGRA. We show that direct and/or indirect detection of neutralino dark matter should be possible at various current and planned facilities.

• Received 3 December 2004

DOI:https://doi.org/10.1103/PhysRevD.71.095008