Tadpoleinduced electroweak symmetry breaking and pNGB Higgs models
Abstract
We investigate induced electroweak symmetry breaking (EWSB) in models in which the Higgs is a pseudoNambuGoldstone boson (pNGB). In pNGB Higgs models, Higgs properties and precision electroweak measurements imply a hierarchy between the EWSB and global symmetrybreaking scales, $$v_H \ll f_H$$. When the pNGB potential is generated radiatively, this hierarchy requires finetuning to a degree of at least $$\sim v_H^2/f_H^2$$. We show that if Higgs EWSB is induced by a tadpole arising from an auxiliary sector at scale $$f_\Sigma \ll v_H$$, this tuning is significantly ameliorated or can even be removed. We present explicit examples both in Twin Higgs models and in Composite Higgs models based on $SO(5)/SO(4)$. For the Twin case, the result is a fully natural model with $$f_H \sim 1$$ TeV and the lightest colored top partners at 2 TeV. These models also have an appealing mechanism to generate the scales of the auxiliary sector and Higgs EWSB directly from the scale $$f_H$$, with a natural hierarchy $$f_\Sigma \ll v_H \ll f_H \sim{\rm TeV}$$. Finally, the framework predicts modified Higgs coupling as well as new Higgs and vector states at LHC13.
 Authors:
 Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
 Publication Date:
 Research Org.:
 Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC), High Energy Physics (HEP) (SC25)
 OSTI Identifier:
 1289920
 Report Number(s):
 FERMILABPUB16076T; arXiv:1603.03772
Journal ID: ISSN 10298479; 1427419
 Grant/Contract Number:
 AC0207CH11359
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Journal of High Energy Physics (Online)
 Additional Journal Information:
 Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2017; Journal Issue: 3; Journal ID: ISSN 10298479
 Publisher:
 Springer Berlin
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Beyond Standard Model; Higgs physics; technicolor and composite models
Citation Formats
Harnik, Roni, Howe, Kiel, and Kearney, John. Tadpoleinduced electroweak symmetry breaking and pNGB Higgs models. United States: N. p., 2017.
Web. doi:10.1007/JHEP03(2017)111.
Harnik, Roni, Howe, Kiel, & Kearney, John. Tadpoleinduced electroweak symmetry breaking and pNGB Higgs models. United States. doi:10.1007/JHEP03(2017)111.
Harnik, Roni, Howe, Kiel, and Kearney, John. Wed .
"Tadpoleinduced electroweak symmetry breaking and pNGB Higgs models". United States.
doi:10.1007/JHEP03(2017)111. https://www.osti.gov/servlets/purl/1289920.
@article{osti_1289920,
title = {Tadpoleinduced electroweak symmetry breaking and pNGB Higgs models},
author = {Harnik, Roni and Howe, Kiel and Kearney, John},
abstractNote = {We investigate induced electroweak symmetry breaking (EWSB) in models in which the Higgs is a pseudoNambuGoldstone boson (pNGB). In pNGB Higgs models, Higgs properties and precision electroweak measurements imply a hierarchy between the EWSB and global symmetrybreaking scales, $v_H \ll f_H$. When the pNGB potential is generated radiatively, this hierarchy requires finetuning to a degree of at least $\sim v_H^2/f_H^2$. We show that if Higgs EWSB is induced by a tadpole arising from an auxiliary sector at scale $f_\Sigma \ll v_H$, this tuning is significantly ameliorated or can even be removed. We present explicit examples both in Twin Higgs models and in Composite Higgs models based on $SO(5)/SO(4)$. For the Twin case, the result is a fully natural model with $f_H \sim 1$ TeV and the lightest colored top partners at 2 TeV. These models also have an appealing mechanism to generate the scales of the auxiliary sector and Higgs EWSB directly from the scale $f_H$, with a natural hierarchy $f_\Sigma \ll v_H \ll f_H \sim{\rm TeV}$. Finally, the framework predicts modified Higgs coupling as well as new Higgs and vector states at LHC13.},
doi = {10.1007/JHEP03(2017)111},
journal = {Journal of High Energy Physics (Online)},
number = 3,
volume = 2017,
place = {United States},
year = {Wed Mar 22 00:00:00 EDT 2017},
month = {Wed Mar 22 00:00:00 EDT 2017}
}
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