Electroweak Baryogenesis And The Fermi Gamma-Ray Line

Abstract

Many particle physics models attempt to explain the 130 GeV gamma-ray feature that the Fermi-LAT observes in the Galactic Center. Neutralino dark matter in non-minimal supersymmetric models, such as the NMSSM, is an especially well-motivated theoretical setup which can explain the line. We explore the possibility that regions of the NMSSM consistent with the 130 GeV line can also produce the observed baryon asymmetry of the universe via electroweak baryogenesis. We find that such regions can in fact accommodate a strongly first-order electroweak phase transition (due to the singlet contribution to the effective potential), while also avoiding a light stop and producing a Standard Model-like Higgs in the observed mass range. Simultaneously, CP-violation from a complex phase in the wino-higgsino sector can account for the observed baryon asymmetry through resonant sources at the electroweak phase transition, while satisfying current constraints from dark matter, collider, and electric dipole moment (EDM) experiments. This result is possible by virtue of a relatively light pseudoscalar Higgs sector with a small degree of mixing, which yields efficient s-channel resonant neutralino annihilation consistent with indirect detection constraints, and of the moderate values of $\mu$ required to obtain a bino-like LSP consistent with the line. The wino mass is essentially a free parameter which one can tune to satisfy electroweak baryogenesis. Thus, the NMSSM framework can potentially explain the origins of both baryonic and dark matter components in the Universe. The tightness of the constraints we impose on this scenario makes it extraordinarily predictive, and conclusively testable in the near future by modest improvements in EDM and dark matter search experiments.

33 pages, 5 figures, 1 table. Submitted to PRD

References in corpus (12)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC
• Dark Matter Results from 225 Live Days of XENON100 Data
• An Improved Experimental Limit on the Electric Dipole Moment of the Neutron
• Improved limit on the permanent electric dipole moment of 199Hg
• Indirect search for dark matter with micrOMEGAs2.4
• The Baryogenesis Window in the MSSM
• Electric Dipole Moments in the MSSM Reloaded
• Electroweak Phase Transition and Baryogenesis in the nMSSM
• Gravity Waves from a Cosmological Phase Transition: Gauge Artifacts and Daisy Resummations
• Yukawa and Tri-scalar Processes in Electroweak Baryogenesis
• Yukawa Interactions and Supersymmetric Electroweak Baryogenesis