Leptoquarks in oblique corrections and Higgs signal strength: status and prospects

107

We perform a complete study of the low-energy phenomenology of S1 and S3 leptoquarks, aimed at addressing the observed deviations in B-meson decays and the muon magnetic dipole moment. Leptoquark contributions to observables are computed at one-loop accuracy in an effective field theory approach, using the recently published complete one-loop matching of these leptoquarks to the Standard Model effective field theory. We present several scenarios, discussing in each case the preferred parameter space and the most relevant observables.

Section: Scenarios and Resultsmentioning

confidence: 99%

Section: Jhep01(2021)138mentioning

confidence: 99%

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Low-energy phenomenology of scalar leptoquarks at one-loop accuracy

Gherardi

Marzocca

Venturini

2021

107

“…Ref. [457] examined the Higgs decays h → γγ, h → gg and h → Zγ, and showed that the scalar leptoquarks contributions to these can generally be measured with increased precision at the ILC, CLIC, CEPC, FCC-ee and FCC-hh. They also showed that the value of the electroweak oblique observables, S and T (but not U ), can change due to leading order contributions from scalar leptoquarks.…”

Section: Jhep09(2021)080mentioning

confidence: 99%

New physics explanations of aμ in light of the FNAL muon g − 2 measurement

Athron

Balázs

Jacob

et al. 2021

216

105

The Fermilab Muon g −2 experiment recently reported its first measurement of the anomalous magnetic moment $$ {a}_{\mu}^{\mathrm{FNAL}} $$ a μ FNAL , which is in full agreement with the previous BNL measurement and pushes the world average deviation $$ \Delta {a}_{\mu}^{2021} $$ ∆ a μ 2021 from the Standard Model to a significance of 4.2σ. Here we provide an extensive survey of its impact on beyond the Standard Model physics. We use state-of-the-art calculations and a sophisticated set of tools to make predictions for aμ, dark matter and LHC searches in a wide range of simple models with up to three new fields, that represent some of the few ways that large ∆aμ can be explained. In addition for the particularly well motivated Minimal Supersymmetric Standard Model, we exhaustively cover the scenarios where large ∆aμ can be explained while simultaneously satisfying all relevant data from other experiments. Generally, the aμ result can only be explained by rather small masses and/or large couplings and enhanced chirality flips, which can lead to conflicts with limits from LHC and dark matter experiments. Our results show that the new measurement excludes a large number of models and provides crucial constraints on others. Two-Higgs doublet and leptoquark models provide viable explanations of aμ only in specific versions and in specific parameter ranges. Among all models with up to three fields, only models with chirality enhancements can accommodate aμ and dark matter simultaneously. The MSSM can simultaneously explain aμ and dark matter for Bino-like LSP in several coannihilation regions. Allowing under abundance of the dark matter relic density, the Higgsino- and particularly Wino-like LSP scenarios become promising explanations of the aμ result.

“…Leptoquarks have been also considered in connection with the phenomenology of the Higgs boson in refs. [5][6][7][8]. It is well known that within the SM and in the present experiments, the multiple Higgs production process is the only way to access the interactions provided by the potential responsible for the spontaneous breaking of the Electroweak (EW) gauge symmetry.…”

Section: Introductionmentioning

confidence: 99%

Enhancement of the double Higgs production via leptoquarks at the LHC

Rold

Epele

Medina

et al. 2021

Measurements of single Higgs production and its decays are in good agreement with the Standard Model. There is still room for large modifications in double Higgs production at LHC, though these effects may be correlated with large corrections to other observables, in particular single Higgs production. In this work we address the issue of enhancing double Higgs production in the presence of scalar leptoquarks while satisfying all experimental constraints. We show at leading order that including more than one species of leptoquarks, large cubic interactions with the Higgs can lead to sizable enhancement of di-Higgs production cross section at LHC, while at the same time keeping other Higgs observables and precision measurements under control. For masses above 800 GeV these corrections are in general below 30%, whereas in a viable scenario in which one of the leptoquarks can be light, specifically in the mass range 400 − 600 GeV, we show that it is possible to roughly double the SM cross section for di-Higgs production, implying that possible first hints of it may be probed at the high luminosity LHC at $$ \mathcal{L} $$ L ∼ 2 ab−1.