Searches for C P -violating dimension-6 electroweak gauge boson operators

132

164

We compute the one-loop matching between the Standard Model Effective Field Theory and the low-energy effective field theory below the electroweak scale, where the heavy gauge bosons, the Higgs particle, and the top quark are integrated out. The complete set of matching equations is derived including effects up to dimension six in the power counting of both theories. We present the results for general flavor structures and include both the CP -even and CP -odd sectors. The matching equations express the masses, gauge couplings, as well as the coefficients of dipole, three-gluon, and four-fermion operators in the low-energy theory in terms of the parameters of the Standard Model Effective Field Theory. Using momentum insertion, we also obtain the matching for the CP -violating theta angles. Our results provide an ingredient for a model-independent analysis of constraints on physics beyond the Standard Model. They can be used for fixed-order calculations at one-loop accuracy and represent a first step towards a systematic next-to-leading-log analysis. E SMEFT operator basis 56 F LEFT operator basis 58 G Conventions for the supplemental material 59 References 61

Section: Resultssupporting

confidence: 81%

“…Here we use the operator as defined inTable 2, while in parts of the literature an operator ∝ F µν W + νρ W − ρ µ was used to compute the matching onto the dipoles[105,107,108]. Note that the latter definition corresponds to the triple-gauge coupling defined in[109].…”

mentioning

confidence: 99%

Low-energy effective field theory below the electroweak scale: matching at one loop

Dekens

Stoffer

2019

132

164

“…In particular, finite 1-loop contributions can be shifted from the matching to the 4-fermion operators into the EDM operators O eB and O eW and vice versa. 8 As already mentioned, for our analysis we choose the scalar-current form for the 4-fermion operators, (L L e R )(ΨΨ). Therefore no finite one-loop contributions arise for the electron EDM from the O ledq and O leē l operators.…”

Section: )mentioning

confidence: 99%

EFT approach to the electron electric dipole moment at the two-loop level

Panico

Pomarol

Riembau

2019

108

The ACME collaboration has recently reported a new bound on the electric dipole moment (EDM) of the electron, |d e | < 1.1 × 10 −29 e · cm at 90% confidence level, reaching an unprecedented accuracy level. This can translate into new relevant constraints on theories beyond the SM laying at the TeV scale, even when they contribute to the electron EDM at the two-loop level. We use the EFT approach to classify these corrections, presenting the contributions to the anomalous dimension of the CP-violating dipole operators of the electron up to the two-loop level. Selection rules based on helicity and CP play an important role to simplify this analysis. We use this result to provide new bounds on BSM with leptoquarks, extra Higgs, or constraints in sectors of the MSSM and composite Higgs models. The new ACME bound pushes natural theories significantly more into fine-tune territory, unless they have a way to accidentally preserve CP.

“…generates the EDM operator for a fermion ψ [37,38]. For the case of the neutron we use the form factors of [39] and we obtain…”

Section: Bounds From Edmsmentioning

confidence: 99%

Precision diboson measurements at hadron colliders

Azatov

Barducci

Venturini

2019

We discuss the measurements of the anomalous triple gauge couplings at Large Hadron Collider focusing on the contribution of the O 3W and O 3W operators. These deviations were known to be particularly hard to measure due to their suppressed interference with the SM amplitudes in the inclusive processes, leading to approximate flat directions in the space of these Wilson coefficients. We present the prospects for the measurements of these interactions at HL-LHC and HE-LHC using exclusive variables sensitive to the interference terms and taking carefully into account effects appearing due to NLO QCD corrections.