John M. Cornwall, Alexander Kusenko, Lauren Pearce, R. D. Peccei
If the particle recently discovered at the LHC is the lightest Higgs boson, it is heavy enough to raise a concern as to whether low-energy supersymmetry as in, for example, the minimal supersymmetric standard model (MSSM), is consistent with the 125 GeV mass of the Higgs boson. A number of solutions have been proposed to relax the MSSM upper bound on the mass of the lightest Higgs boson. Here we explore the possibility that the trilinear supersymmetry breaking terms can be large enough for the formation of bound states of squarks via the Higgs boson exchange. Such bound states can appear in the low-energy effective theory as additional Higgs bosons, and they can mix with the fundamental Higgs boson. Furthermore, supersymmetry breaking can trigger electroweak symmetry breaking by formation of such bound states with non-zero vacuum expectation values. In the resulting vacuum, the usual relation between the gauge couplings and the Higgs self-coupling does not apply, and there is no reason to expect the same upper bound on the mass of the lightest Higgs boson. We explore the bound states using the Bethe-Salpeter (BS) equation whose lowest-order kernel is a one-loop crossed box graph, and calculate the minimal value of the tri-linear coupling required for the formation of the bound states using a variational approach. The result is about 2.5 times the value at which one-loop corrections in the MSSM give a maximum Higgs mass.
View original:
http://arxiv.org/abs/1210.6433
No comments:
Post a Comment