Could there be a Fourth Generation?
arXiv:hep-ph/0203146
Abstract
We investigate the possibility of incorporating a chiral fourth generation into a GUT model. We find that in order to do so, precision fits to electroweak observables demand the introduction of light (< M_Z) supersymmetric particles. This also enables us to provide decay channels to the fourth-generation quarks. Perturbative consistency sets an upper bound on the coloured supersymmetric spectrum. The upper limit on the lightest Higgs boson is calculated and found to be above the present experimental lower limit.
12 pages, LaTeX, 1 figure, updated and slightly extended version of an article contributed to Holger Bech Nielsen's Festscript
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