Effective description of general extensions of the Standard Model: the complete tree-level dictionary

A complete one-loop matching calculation for real singlet scalar extensions of the Standard Model to the Standard Model effective field theory (SMEFT) of dimension-six operators is presented. We compare our analytic results obtained by using Feynman diagrams to the expressions derived in the literature by a combination of the universal one-loop effective action (UOLEA) approach and Feynman calculus. After identifying contributions that have been overlooked in the existing calculations, we find that the pure diagrammatic approach and the mixed method lead to identical results. We highlight some of the subtleties involved in computing one-loop matching corrections in SMEFT. arXiv:2003.05936v2 [hep-ph]

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“…The results (3.6) and (3.7) are well-known and agree with the analytic expressions reported for instance in the works [14,16,29].…”

Section: Tree-level Resultssupporting

confidence: 90%

Singlet night in Feynman-ville: one-loop matching of a real scalar

Haisch

Ruhdorfer

Salvioni

et al. 2020

J. High Energ. Phys.

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“…Since it was shown in Section 3.4 that the only viable operators are of type O (1) qu and O (1) qd , the conceivable tree-level mediators, excluding fields that admit baryon number violating diquark couplings 11 , are (see e.g. [110])…”

Section: Lepton Flavour Universal C 9 From Leptophobic Mediatorsmentioning

confidence: 99%

B-decay discrepancies after Moriond 2019

et al. 2020

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Following the updated measurement of the lepton flavour universality (LFU) ratio R K in B → K decays by LHCb, as well as a number of further measurements, e.g. R K * by Belle and B s → µµ by ATLAS, we analyse the global status of new physics in b → s transitions in the weak effective theory at the b-quark scale, in the Standard Model effective theory above the electroweak scale, and in simplified models of new physics. We find that the data continues to strongly prefer a solution with new physics in semi-leptonic Wilson coefficients. A purely muonic contribution to the combination C 9 = −C 10 , well suited to UV-complete interpretations, is now favoured with respect to a muonic contribution to C 9 only. An even better fit is obtained by allowing an additional LFU shift in C 9 . Such a shift can be renormalization-group induced from four-fermion operators above the electroweak scale, in particular from semi-tauonic operators, able to account for the potential discrepancies in b → c transitions. This scenario is naturally realized in the simplified U 1 leptoquark model. We also analyse simplified models where a LFU effect in b → s is induced radiatively from four-quark operators and show that such a setup is on the brink of exclusion by LHC di-jet resonance searches.

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“…The Wilson coefficients c (d) i encode the virtual effects of the heavy new physics in low-energy observables. Their precise form in terms of masses and couplings of the new particles can be obtained via matching with the ultraviolet (UV) completion of the SM [26], or inferred using power-counting rules [27,28].…”

Section: Effective Field Theory Description Of Higgs Boson Couplingsmentioning

confidence: 99%

Higgs Boson studies at future particle colliders

Blas

Cepeda

D’Hondt

et al. 2020

J. High Energ. Phys.

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303

353

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This document aims to provide an assessment of the potential of future colliding beam facilities to perform Higgs boson studies. The analysis builds on the submissions made by the proponents of future colliders to the European Strategy Update process, and takes as its point of departure the results expected at the completion of the HL-LHC program. This report presents quantitative results on many aspects of Higgs physics for future collider projects using uniform methodologies for all proposed machine projects of sufficient maturity. This report is still preliminary and is distributed for the purposes of discussion at the Open Symposium in Granada (13-16/05/2019). 2/583/58 9/58 10/58 15/58 16 In fact, the width and the branching ratio to undetected final states are not independent observables. In the analysis presented in Section 3.2 we opted to fit BR unt and calculate Γ H from Eq. (4).

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Effective description of general extensions of the Standard Model: the complete tree-level dictionary

Cited by 226 publications

References 81 publications

Singlet night in Feynman-ville: one-loop matching of a real scalar

Singlet night in Feynman-ville: one-loop matching of a real scalar

B-decay discrepancies after Moriond 2019

Higgs Boson studies at future particle colliders

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