Higgs, top quark, and electroweak precision measurements at future 
e+e−
 colliders: A combined effective field theory analysis with renormalization mixing

Abstract We study the forward-backward asymmetry AFB in pp → ℓ+ℓ− at the Z peak within the Standard Model Effective Field Theory (SMEFT). We find that this observable provides per mille level constraints on the vertex corrections of the Z boson to quarks, which close a flat direction in the electroweak precision SMEFT fit. Moreover, we show that current AFB data is precise enough so that its inclusion in the fit improves significantly LEP bounds even in simple New Physics setups. This demonstrates that the LHC can compete with and complement LEP when it comes to precision measurements of the Z boson properties.

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Effective field theory analysis of dark matter-standard model interactions with spin one mediators

Journal of High Energy Physics ◽

10.1007/jhep02(2021)223 ◽

2021 ◽

Vol 2021 (2) ◽

Author(s):

Fabiola Fortuna ◽

Pablo Roig ◽

José Wudka

Keyword(s):

Field Theory ◽

Dark Matter ◽

Standard Model ◽

Effective Field Theory ◽

Gamma Ray ◽

Direct Detection ◽

Effective Field ◽

Indirect Detection ◽

Theory Analysis ◽

Invisible Decay

Abstract We analyze interactions between dark matter and standard model particles with spin one mediators in an effective field theory framework. In this paper, we are considering dark particles masses in the range from a few MeV to the mass of the Z boson. We use bounds from different experiments: Z invisible decay width, relic density, direct detection experiments, and indirect detection limits from the search of gamma-ray emissions and positron fluxes. We obtain solutions corresponding to operators with antisymmetric tensor mediators that fulfill all those requirements within our approach.

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Precision Higgs couplings in neutral naturalness models: an effective field theory approach

Journal of High Energy Physics ◽

10.1007/jhep02(2021)234 ◽

2021 ◽

Vol 2021 (2) ◽

Author(s):

Lucien Heurtier ◽

Hao-Lin Li ◽

Huayang Song ◽

Shufang Su ◽

Wei Su ◽

...

Keyword(s):

Field Theory ◽

Effective Field Theory ◽

Goldstone Boson ◽

Higgs Sector ◽

New Physics ◽

Effective Field ◽

Precision Measurements ◽

Global Symmetry ◽

Theory Approach ◽

Decay Channels

AbstractThe Higgs sector in neutral naturalness models provides a portal to the hidden sectors, and thus measurements of Higgs couplings at current and future colliders play a central role in constraining the parameter space of the model. We investigate a class of neutral naturalness models, in which the Higgs boson is a pseudo-Goldstone boson from the universal SO(N)/SO(N −1) coset structure. Integrating out the radial mode from the spontaneous global symmetry breaking, we obtain various dimension-six operators in the Standard Model effective field theory, and calculate the low energy Higgs effective potential with radiative corrections included. We perform aχ2fit to the Higgs coupling precision measurements at current and future colliders and show that the new physics scale could be explored up to 2.3 (2.4) TeV without (with) the Higgs invisible decay channels at future Higgs factories. The limits are comparable to the indirect constraints obtained via electroweak precision measurements.

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