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arXiv · 0706.3718

Four Generations and Higgs Physics

Graham D. Kribs·Tilman Plehn·Michael Spannowsky·Tim M. P. Tait
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Abstract

In the light of the LHC, we revisit the implications of a fourth generation of chiral matter. We identify a specific ensemble of particle masses and mixings that are in agreement with all current experimental bounds as well as minimize the contributions to electroweak precision observables. Higgs masses between 115-315 (115-750) GeV are allowed by electroweak precision data at the 68% and 95% CL. Within this parameter space, there are dramatic effects on Higgs phenomenology: production rates are enhanced, weak-boson-fusion channels are suppressed, angular distributions are modified, and Higgs pairs can we observed. We also identify exotic signals, such as Higgs decay to same-sign dileptons. Finally, we estimate the upper bound on the cutoff scale from vacuum stability and triviality.

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Graham D. Kribs, Tilman Plehn, Michael Spannowsky, Tim M. P. Tait. 2007-06-26. Four Generations and Higgs Physics. https://doi.org/10.1103/physrevd.76.075016

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