MSSM Baryogenesis and Electric Dipole Moments: An Update on the Phenomenology

TL;DR

This paper investigates the implications of MSSM electroweak baryogenesis for electric dipole moment searches, identifying parameter space regions that will be tested by upcoming experiments, thus providing a crucial test of the model.

Contribution

It expands previous MSSM baryogenesis studies by analyzing the (tanβ, m_A) parameter space and non-universal CP phases, establishing lower bounds on EDMs within this framework.

Findings

Lower EDM limits are comparable to upcoming experimental sensitivities.

MSSM electroweak baryogenesis can be conclusively tested soon.

Parameter space regions compatible with baryogenesis predict detectable EDMs.

Abstract

We explore the implications of electroweak baryogenesis for future searches for permanent electric dipole moments in the context of the minimal supersymmetric extension of the Standard Model (MSSM). From a cosmological standpoint, we point out that regions of parameter space that over-produce relic lightest supersymmetric particles can be salvaged only by assuming a dilution of the particle relic density that makes it compatible with the dark matter density: this dilution must occur after dark matter freeze-out, which ordinarily takes place after electroweak baryogenesis, implying the same degree of dilution for the generated baryon number density as well. We expand on previous studies on the viable MSSM regions for baryogenesis, exploring for the first time an orthogonal slice of the relevant parameter space, namely the (tan\beta, m_A) plane, and the case of non-universal relative gaugino-higgsino CP violating phases. The main result of our study is that in all cases lower limits on the size of the electric dipole moments exist, and are typically on the same order, or above, the expected sensitivity of the next generation of experimental searches, implying that MSSM electroweak baryogenesis will be soon conclusively tested.