Conveners
Session: Opening and multiboson
- Ilaria Brivio (University & INFN Bologna)
Session: Precision
- Ramona Groeber (Universitร di Padova and INFN, Sezione di Padova)
Session: Matching
- Ken Mimasu (University of Southampton)
Session: Top
- Davide Pagani (Universita e INFN, Bologna (IT))
Session: Amplitudes and on-shell methods
- Gauthier Durieux (CP3 - UCLouvain)
Session: RGE, flavor, four-fermion operators
- Celine Catherine A Degrande
Session: ALPs, BSM connection, geometry
- Adam Orion Martin (University of Notre Dame (US))
Session: HEFT and dimension 8
- Gudrun Heinrich (KIT)
Session: Fits
- Eleni Vryonidou (University of Manchester (GB))
Session: New perspectives
- Fabio Maltoni (Universite Catholique de Louvain (UCL) (BE) and Universitร di Bologna)
This study explores fully leptonic WZ and WW production within the SMEFT framework at NLO in QCD, focusing on both CP-even and CP-odd triple gauge coupling dimension-six operators. We investigate the off-shell production processes and contrast our findings with those derived under the narrow-width approximation. Alongside the conventional kinematical observables, we examine...
Below the electroweak scale, the LEFT provides a systematic approximation of both heavy SM and BSM physics. When extending the LEFT to next-to-leading-log accuracy, a number of technical challenges arise. In this talk, I will discuss the basis construction in the 't Hooft-Veltman scheme, $\gamma_5$ and evanescent operators, the restoration of chiral symmetry, and the role of redundant...
In Effective Field Theories, evanescent operators are introduced to compensate for the breakdown of four-dimensional Dirac identities (e.g. Fierz Identities) when used in combination with dimensional regularization.
In this talk, we provide an alternative approach where contributions of evanescent operators are viewed as corrections to d=4 Dirac relations. This new perspective not only...
We present a calculation of the four-top quark operator contributions to Higgs production via gluon fusion in the Standard Model Effective Field Theory. The four-top operators enter for the first time via two-loop diagrams. Due to their chiral structure they contain $\gamma_5$, so special care needs to be taken when using dimensional regularisation for the loop integrals. We use two different...
There has been much progress in performing and understanding EFT matching at the one-loop order in the last decade; however, the methods have rarely been applied to the case of spontaneously broken gauge theories. In this talk, I reexamine the role of gauge symmetries in EFT matching. It is possible to prove the validity of the hard-region matching formula when using the background field (BF)...
We study the effects of four-heavy-quark operators in the production of top quarks in the framework of the Standard Model Effective Field Theory (SMEFT) at the LHC. In particular, we compute for the first time the total contribution of the four-top-quark operator which enters only at the one-loop level in the top-quark pair production process. Analytical results at one-loop are presented for...
Being the heaviest fermion and having a Yukawa interaction almost equal to one, the top-quark represents one of the most interesting portals to New Physics (NP). If it is light or belongs to a secluded sector, NP can be difficult to detect in colliders with traditional methods. An alternative way, at least for setting bounds, is studying the virtual corrections to SM processes. Kinematical...
The effective field theory is an important approach for systematically parameterizing new physics beyond the Standard Model. A central concern in effective field theory is constructing effective operator bases. This work focuses on studying operator bases in effective field theory. I will introduce a general method for constructing on-shell operator bases and off-shell Green's bases in...
We construct an effective field theory for non-relativistic heavy dark matter of arbitrary spin based on the Little group formalism. We present the most general HDMEFT basis up to dimension seven and show that it reproduces the non-relativistic spin 1/2 case presented in the literature. We also discuss the matching onto the relativistic DM EFT.
We elaborate on the application of on-shell and unitarity-based methods for evaluating renormalization group coefficients, and generalize this framework to account for the mixing of operators with different dimensions and leading mass effects. We derive a master formula for anomalous dimensions stemming from the general structure of operator mixings, up to two-loop order, and show how the...
The Standard Model Effective Field Theory serves as a widely utilized framework for exploring new physics (NP) effects in a model-independent manner.
In previous studies, Drell-Yan collider data has stood out as a promising signature due to its energy enhancement relative to Standard Model predictions.
In our investigation, we expand on this, by analyzing the "missing energy + jet"...
CP-violating probes are among the most promising and yet relatively unexplored ways to look for Axion-like particles (ALPs) and to investigate their phenomenology.
Starting from the most general dimension-5, $SU(3)_{\text{c}} \times U(1)_{\text{em}}$ invariant effective Lagrangian for a CP-violating ALP at the electroweak (EW) scale, we discuss two relevant phenomenological frameworks.
In...
We discuss heavy particles that can be used to pin down the faithful Standard Model (SM) gauge group and their patterns in the SM effective field theory (SMEFT). These heavy particles are not invariant under a specific $\mathbb{Z}_6$ subgroup of $SU(3)_c\times SU(2)_L \times U(1)_Y$, which however acts trivially on all the SM particles, hence the faithful SM gauge group remains undetermined....
We match the Minimal Supersymmetric Standard Model (MSSM) onto its corresponding low-energy EFTs at one loop. For this purpose, we consider several scenarios: (i) matching the full MSSM onto SMEFT; (ii) integrating out only the lightest of the BSM states (such as the stops, sbottoms, gaugeinos, and Higgsinos), while neglecting the heavier states; (iii) integrating out only the heavy states,...
Field space geometry has been fruitful in understanding many aspects of EFT, including basis-independent criteria for distinguishing HEFT vs. SMEFT, reorganization of scattering amplitudes in covariant form, derivation of renormalization group equations and geometric soft theorem. We incorporate field space geometry in functional matching by dividing the field space into light and heavy...
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Some selected aspects of Bosonic HEFT with implications for multiple Higgs production at colliders will be presented. These include: 1) Recent progress on renormalization of 1PI functions and practical applications for specific processes at colliders, 2) The approach of matching UV theories to HEFT by identifying their predictions for amplitudes: the 2HDM case and its non-decoupling...
The absence of newly discovered states at high energies makes the use of Effective Field Theories (EFTs) the adequate tool to describe the electroweak sector. Within the available EFTs, the Higgs Effective Field Theory (HEFT) provides the most general parametrization of electroweak physics. In this context, effects of new physics can substantially modify the lowest-order couplings of HEFT and...
The measurements of off-shell Higgs boson contributions in massive gauge boson pair production are known to probe its electroweak interactions across different energy scales. These are often employed as an estimator of the Higgs boson width in restricted theories of beyond the Standard Model physics. In this talk, I will revisit this measurement in the context of the Higgs Effective Field...
I will discuss a forthcoming paper on the convergence of the SMEFT expansion in the specific case of Drell Yan. By using some top down examples I will show how realistic the use of data binned in energy to better constrain Wilson coefficients is, and when this approach fails. I will also explore when dimension-six squared terms improve the quality of (simplified) fits and when this approach...
We present results from a global fit of dimension-six SMEFT operators that includes electroweak, Higgs-boson, top-quark, and flavor observables. The leading-order scale dependence of the SMEFT Wilson coefficients is consistently included in the evolution from the UV scale to the electroweak scale and the low-energy scale of flavor observables. In defining the SMEFT set of active operators we...
The interpretation of hadron collider, such as the LHC, data, and the assessment of possible hints of new physics, require the precise knowledge of the proton structure in terms of parton distribution functions (PDFs). In this talk, I present a systematic methodology designed to determine whether and how global PDF fits might inadvertently 'fit away' signs of new physics, described by...
The ongoing Effective Field Theory (EFT) program at the LHC and elsewhere is motivated by streamlining the connection between experimental data and UV-complete scenarios of heavy new physics beyond the Standard Model (BSM). This connection is provided by matching relations mapping the Wilson coefficients of the EFT to the couplings and masses of UV-complete models. Building upon recent work on...
The upcoming launch of the LISA interferometer has recently strengthened the interest in exploring SM extensions where a gravitational wave-producing, strong first-order electroweak phase transition (SFOEWPT) occurs in the early universe. One of the preferred approaches to the study of thermal FOPTs is through the construction of a dimensionally reduced effective field theory (3dEFT) where the...
