Exploring CP violation in the MSSM

We explore the prospects for observing CP violation in the minimal supersymmetric extension of the Standard Model (MSSM) with six CP-violating parameters, three gaugino mass phases and three phases in trilinear soft supersymmetry-breaking parameters, using the CPsuperH code combined with a geometric approach to maximise CP-violating observables subject to the experimental upper bounds on electric dipole moments. We also implement CP-conserving constraints from Higgs physics, flavour physics and the upper limits on the cosmological dark matter density and spin-independent scattering. We study possible values of observables within the constrained MSSM (CMSSM), the non-universal Higgs model (NUHM), the CPX scenario and a variant of the phenomenological MSSM (pMSSM). We find values of the CP-violating asymmetry ACP in b→sγ decay that may be as large as 3 %, so future measurements of ACP may provide independent information about CP violation in the MSSM. We find that CP-violating MSSM contributions to the Bs meson mass mixing term ΔMBs are in general below the present upper limit, which is dominated by theoretical uncertainties. If these could be reduced, ΔMBs could also provide an interesting and complementary constraint on the six CP-violating MSSM phases, enabling them all to be determined experimentally, in principle. We also find that CP violation in the h2,3τ+τ- and h2,3t¯t couplings can be quite large, and so may offer interesting prospects for future pp , e+e- , μ+μ- and γγ colliders