More on electric dipole moment constraints on phases in the constrained MSSM

摘要

We reconsider constraints on CP-violating phases in mSUGRA, sometimes also referred to as the Constrained Minimal Supersymmetric Standard Model. We include the recent calculations of Ibrahim and Nath on the chromoelectric and purely gluonic contributions to the quark electric dipole moment and combine cosmological limits on gaugino masses with experimental bounds on the neutron (and electron) electric dipole moments. The constraint on the phase of the Higgs mixing mass mu,theta(mu), is dependent on the value of the trilinear mass parameter, A, in the model and on tan beta. For values of A < 300 GeV at the GUT scale, we find theta(mu)/ pi less than or similar to 0.05, while for A < 1500GeV, theta(mu)/ pi less than or similar to 0.3. Thus, we find that in principle, large CP violating phases are compatible with the bounds on the electric dipole moments of the neutron and electron, as well as remaining compatible with the cosmological upper bound on the relic density of neutralinos. The other CP-violating phase theta(A) is essentially unconstrained. (C) 1998 Elsevier Science B.V. All rights reserved. References: 43