Standard Model Extended by a Heavy Singlet: Linear vs. Nonlinear EFT

G. Buchalla; O. Cata; A. Celis; C. Krause

doi:10.1016/j.nuclphysb.2017.02.006

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arXiv · 1608.03564

Standard Model Extended by a Heavy Singlet: Linear vs. Nonlinear EFT

G. Buchalla·O. Cata·A. Celis·C. Krause

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Abstract

We consider the Standard Model extended by a heavy scalar singlet in different regions of parameter space and construct the appropriate low-energy effective field theories up to first nontrivial order. This top-down exercise in effective field theory is meant primarily to illustrate with a simple example the systematics of the linear and nonlinear electroweak effective Lagrangians and to clarify the relation between them. We discuss power-counting aspects and the transition between both effective theories on the basis of the model, confirming in all cases the rules and procedures derived in previous works from a bottom-up approach.

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G. Buchalla, O. Cata, A. Celis, C. Krause. 2016-08-11. Standard Model Extended by a Heavy Singlet: Linear vs. Nonlinear EFT. https://doi.org/10.1016/j.nuclphysb.2017.02.006

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