125 GeV Higgs state in the context of four generations with two Higgs doublets

Geller, Michael and Bar-Shalom, Shaouly and Eilam, Gad and Soni, Amarjit (2012) 125 GeV Higgs state in the context of four generations with two Higgs doublets. In: PHYSICAL REVIEW D, 86 (11).

PDF Phys_RevD_86-11_115008_2012.pdf - Published Version Restricted to Registered users only Download (444kB) | Request a copy

Abstract

We interpret the recent discovery of a 125 GeV Higgs-like state in the context of a two-Higgs-doublet model with a heavy fourth sequential generation of fermions, in which one Higgs doublet couples only to the fourth-generation fermions, while the second doublet couples to the lighter fermions of the first three families. This model is designed to accommodate the apparent heaviness of the fourth-generation fermions and to effectively address the low-energy phenomenology of a dynamical electroweak-symmetry-breaking scenario. The physical Higgs states of the model are, therefore, viewed as composites primarily of the fourth-generation fermions. We find that the lightest Higgs, h, is a good candidate for the recently discovered 125 GeV spin-zero particle, when tan beta similar to O(1), for typical fourth-generation fermion masses of M-4G = 400-600 GeV, and with a large t-t' mixing in the right-handed quark sector. This, in turn, leads to BR(t' -> th) similar to O(1), which drastically changes the t' decay pattern. We also find that, based on the current Higgs data, this two-Higgs-doublet model generically predicts an enhanced production rate (compared to the Standard Model) in the pp -> h -> tau tau channel, and reduced rates in the VV -> h -> gamma gamma and p (p) over bar /pp -> V -> hV -> Vbb channels. Finally, the heavier CP-even Higgs is excluded by the current data up to m(H) similar to 500 GeV, while the pseudoscalar state, A, can be as light as 130 GeV. These heavier Higgs states and the expected deviations from the Standard Model din some of the Higgs production channels can be further excluded or discovered with more data.

Item Type:	Journal Article
Publication:	PHYSICAL REVIEW D
Publisher:	AMER PHYSICAL SOC
Additional Information:	Copyright for this article belongs to AMER PHYSICAL SOC, USA
Department/Centre:	Division of Physical & Mathematical Sciences > Centre for High Energy Physics
Date Deposited:	03 Jan 2013 06:46
Last Modified:	03 Jan 2013 06:46
URI:	http://eprints.iisc.ac.in/id/eprint/45574

Actions (login required)

View Item