A golden probe of nonlinear Higgs dynamics

Abstract The most salient generic feature of a composite Higgs boson resides in the nonlinearity of its dynamics, which arises from degenerate vacua associated with the pseudo-Nambu–Goldstone (PNGB) nature of the Higgs boson. It has been shown that the nonlinear Higgs dynamics is universal in the IR...

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Main Authors: Da Liu, Ian Low, Roberto Vega-Morales
Format: Article
Language:English
Published: SpringerOpen 2020-09-01
Series:European Physical Journal C: Particles and Fields
Online Access:http://link.springer.com/article/10.1140/epjc/s10052-020-8244-8
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author Da Liu
Ian Low
Roberto Vega-Morales
author_facet Da Liu
Ian Low
Roberto Vega-Morales
author_sort Da Liu
collection DOAJ
description Abstract The most salient generic feature of a composite Higgs boson resides in the nonlinearity of its dynamics, which arises from degenerate vacua associated with the pseudo-Nambu–Goldstone (PNGB) nature of the Higgs boson. It has been shown that the nonlinear Higgs dynamics is universal in the IR and controlled only by a single parameter f, the decay constant of the PNGB Higgs. In this work we perform a fit, for the first time, to Wilson coefficients of $${\mathcal {O}}(p^4)$$ O ( p 4 ) operators in the nonlinear Lagrangian using the golden H $$\rightarrow $$ → 4L decay channel. By utilizing both the “rate” information in the signal strength and the “shape” information in the fully differential spectra, we provide limits on the Goldstone decay constant f, as well as $${\mathcal {O}}(p^4)$$ O ( p 4 ) Wilson coefficients, using Run 2 data at the LHC. In rate measurements alone, the golden channel prefers a negative $$\xi =v^2/f^2$$ ξ = v 2 / f 2 corresponding to a non-compact coset structure. Including the shape information, we identify regions of parameter space where current LHC constraint on f is still weak, allowing for $$\xi \lesssim 0.5$$ ξ ≲ 0.5 or $$\xi \gtrsim -0.5$$ ξ ≳ - 0.5 . We also comment on future sensitivity at the high-luminosity upgrade of the LHC which could allow for simultaneous fits to multiple Wilson coefficients.
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spelling doaj.art-cc4990c331d846829f1576a5cab2eeb52022-12-22T03:58:27ZengSpringerOpenEuropean Physical Journal C: Particles and Fields1434-60441434-60522020-09-0180911310.1140/epjc/s10052-020-8244-8A golden probe of nonlinear Higgs dynamicsDa Liu0Ian Low1Roberto Vega-Morales2High Energy Physics Division, Argonne National LaboratoryHigh Energy Physics Division, Argonne National LaboratoryCAFPE and Departamento de Física Teórica y del Cosmos, Universidad de GranadaAbstract The most salient generic feature of a composite Higgs boson resides in the nonlinearity of its dynamics, which arises from degenerate vacua associated with the pseudo-Nambu–Goldstone (PNGB) nature of the Higgs boson. It has been shown that the nonlinear Higgs dynamics is universal in the IR and controlled only by a single parameter f, the decay constant of the PNGB Higgs. In this work we perform a fit, for the first time, to Wilson coefficients of $${\mathcal {O}}(p^4)$$ O ( p 4 ) operators in the nonlinear Lagrangian using the golden H $$\rightarrow $$ → 4L decay channel. By utilizing both the “rate” information in the signal strength and the “shape” information in the fully differential spectra, we provide limits on the Goldstone decay constant f, as well as $${\mathcal {O}}(p^4)$$ O ( p 4 ) Wilson coefficients, using Run 2 data at the LHC. In rate measurements alone, the golden channel prefers a negative $$\xi =v^2/f^2$$ ξ = v 2 / f 2 corresponding to a non-compact coset structure. Including the shape information, we identify regions of parameter space where current LHC constraint on f is still weak, allowing for $$\xi \lesssim 0.5$$ ξ ≲ 0.5 or $$\xi \gtrsim -0.5$$ ξ ≳ - 0.5 . We also comment on future sensitivity at the high-luminosity upgrade of the LHC which could allow for simultaneous fits to multiple Wilson coefficients.http://link.springer.com/article/10.1140/epjc/s10052-020-8244-8
spellingShingle Da Liu
Ian Low
Roberto Vega-Morales
A golden probe of nonlinear Higgs dynamics
European Physical Journal C: Particles and Fields
title A golden probe of nonlinear Higgs dynamics
title_full A golden probe of nonlinear Higgs dynamics
title_fullStr A golden probe of nonlinear Higgs dynamics
title_full_unstemmed A golden probe of nonlinear Higgs dynamics
title_short A golden probe of nonlinear Higgs dynamics
title_sort golden probe of nonlinear higgs dynamics
url http://link.springer.com/article/10.1140/epjc/s10052-020-8244-8
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