Heavy Higgs resonances for the neutralino relic density in the Higgs decoupling limit of the CP-noninvariant minimal supersymmetric standard model

Abstract

The lightest neutralino is a compelling candidate to account for cold dark matter in the universe in supersymmetric theories with R-parity. In the CP-invariant theory, the neutralino relic density can be found in accord with recent WMAP data if neutralino annihilation in the early universe occurs via the s-channel A funnel. In contrast, in the CP-noninvariant theory two heavy neutral Higgs bosons can contribute to the Higgs funnel mechanism significantly due to a CP-violating complex mixing between two heavy states, in particular, when they are almost degenerate. With a simple analytic and numerical analysis, we demonstrate that the CP-violating Higgs mixing can modify the profile of the neutralino relic density considerably in the heavy Higgs funnel with the neutralino mass close to half of the heavy Higgs masses. (c) 2006 Elsevier B.V. All rights reserved.