2004/10/06 by K. S. Babu, Babu, K. S., Ilia Gogoladze +3
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #hep-ph
paper · pdf · doi:10.48550/arxiv.hep-ph/0410085
15 pages LaTeX, 4 EPS figures. References added
arxiv created 2004/11/04 · arxiv updated 2009/12/01
Supersymmetric extensions of the Standard Model generally give a theoretical upper limit on the lightest Higgs boson mass which may be uncomfortably close to the current experimental lower bound of mh > 114 GeV. Here we show ways in which this upper limit on mh can be relaxed substantially in the perturbative regime, while maintaining the successful unification of gauge couplings as observed in the minimal scenario. A class of models is presented, which includes new vector-like matter with the quantum numbers of the 5, 5-bar and singlet representations of SU(5) and having Yukawa couplings (κ) to the usual Higgs doublet Hu. This new matter transforms non-trivially under a "lateral" SU(N) gauge symmetry, which enables the new Yukawa couplings κto be sizable, even larger than the top-quark Yukawa coupling, and still be perturbative at all momenta up to the unification scale of 1016 GeV. We find that, consistent with low energy constraints, mh can be raised to values as large as 200 - 300 GeV.