New contributions to neutralino elastic cross sections from<b><i>CP</i></b>violating phases in the minimal supersymmetric standard model

Abstract

We compute the four-Fermi neutralino-quark interaction Lagrangian including\ncontributions from the CP violating phases in the MSSM. We find that\nneutralino-nucleus scattering cross-sections relevant for direct detection\nexperiments show a strong dependence on the value of the CP-violating phase\nassociated with the $\\mu$ parameter, $\\theta_\\mu$. In some cases, for a broad\nrange of non-zero $\\theta_\\mu$, there are cancellations in the cross-sections\nwhich reduce the cross-section by more than an order of magnitude. In other\ncases, there may be enhancements as one varies $\\theta_\\mu$.\n