Article

Unified TeV scale picture of baryogenesis and dark matter.

Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078, USA.
Physical Review Letters (Impact Factor: 7.73). 05/2007; 98(16):161301. DOI: 10.1103/PHYSREVLETT.98.161301
Source: PubMed

ABSTRACT We present a simple extension of the minimal supersymmetric standard model which provides a unified picture of cosmological baryon asymmetry and dark matter. Our model introduces a gauge singlet field N and a color triplet field X which couple to the right-handed quark fields. The out-of-equilibrium decay of the Majorana fermion N mediated by the exchange of the scalar field X generates adequate baryon asymmetry for MN approximately 100 GeV and MX approximately TeV. The scalar partner of N (denoted N1) is naturally the lightest SUSY particle as it has no gauge interactions and plays the role of dark matter. The model is experimentally testable in (i) neutron-antineutron oscillations with a transition time estimated to be around 10(10)sec, (ii) discovery of colored particles X at LHC with mass of order TeV, and (iii) direct dark matter detection with a predicted cross section in the observable range.

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