The calculation of contributions from the chromomagnetic and four-top-quark-operators within Standard Model Effective Field Theory (SMEFT) to Higgs boson pair production in gluon fusion is presented, in combination with NLO QCD corrections. Here we focus on the $γ_5$-scheme dependence introduced by the four-top-quark-operators and the interplay with other operators contributing to this process in SMEFT.
We study four top quark production at hadron colliders in the Standard Model Effective Field Theory (SMEFT). We perform an analysis at the tree-level, including all possible QCD- and EW-coupling orders and relevant dimension-six operators. We find several cases where formally subleading terms give rise to significant contributions, potentially providing sensitivity to a broad class of operators. Inclusive and differential predictions are presented for the LHC and a future $pp$ circular collider operating at $100$ TeV. We estimate the sensitivity of different operators and perform a simplified …
We present results for Higgs boson pair production in gluon fusion at next-to-leading order in QCD, including effects of anomalous couplings within Standard Model Effective Field Theory (SMEFT). In particular, we investigate truncation effects of the SMEFT series, comparing different ways to treat powers of dimension-six operators and double operator insertions.
We present the three-body decay of the Higgs boson into two leptons and a photon to dimension-eight in the Standard Model Effective Field Theory (SMEFT). In order to obtain this result we interfere the full one-loop Standard Model result with the tree-level result in the SMEFT. This is the first calculation of the partial width of the Higgs boson into two leptons and a photon in the SMEFT to incorporate the full one-loop dependence for the Standard Model as well as the full tree level dimension-eight dependence in the SMEFT. We find that this channel can aid in distinguishing strongly interact…
The calculation of next-to-leading order (NLO) perturbative corrections at fixed operator dimension in Standard Model Effective Field Theory (SMEFT) has been a topic of much recent interest. In this paper we obtain the NLO corrections from dimension-6 operators to the Higgs boson decays $h\to f\bar{f}$, where the fermions $f \in \{μ,τ,c\}$. This extends previous results for $h\to b\bar{b}$ to all phenomenologically relevant Higgs boson decays into fermions, and provides the basis for future precision analyses of these decays within effective field theory. We point out the benefits of studying …
Impact of NLO EW and QCD corrections to dimension-6 SMEFT coefficients constraints in Higgs decays
Florida State University(佛罗里达州立大学);Universidad Autónoma de Madrid(马德里自治大学);Brookhaven National Laboratory(布鲁克海文国家实验室);Princeton University(普林斯顿大学);Stockholm University(斯德哥尔摩大学)
The Standard Model effective field theory (SMEFT) provides a general framework to include the dynamics of the beyond standard model physics residing at a certain higher energy scale $Λ$. We study the top-quark production along with a Higgs boson and a jet (tHq) at the LHC experiment within the framework of the SMEFT. First, identifying the relevant sensitive dimension-6 SMEFT operators, a strategy is developed to constrain the Wilson Coefficients (WC) corresponding to these associated SMEFT operators using the latest LHC measurements, providing a complementary way to the global-fit approach. T…
We present a study of four top quark production at the LHC in the Standard Model Effective Field Theory (SMEFT). The analysis is performed at the tree-level, including all terms from the mixed QCD-EW-coupling cross-section expansion and all the relevant dimension-six SMEFT operators. We find several cases in which formally subleading terms give rise to significant contributions. Moreover, we obtain limits on the SMEFT Wilson coefficients (WCs), including different collider setups, FCC-hh and HL-LHC, using a simplified chi-square fit. Through the latter, we also assessed the importance of inclu…
The Standard Model Effective Field Theory (SMEFT) provides a powerful theoretical framework for searching for subtle deviations from the Standard Model. In this talk, we present the results from a global fit of the dimension-6 operators of the SMEFT to a combination of Higgs, top, diboson and electroweak precision observables. SMEFT constraints driven by data from the top quark sector are highlighted. We explore the interplay between the top and Higgs sectors, emphasising the need for a global approach to constraining the SMEFT.
NLO EW and QCD dimension-6 SMEFT results for Higgs and gauge boson decays in POPxf format
Florida State University(佛罗里达州立大学);Brookhaven National Laboratory(布鲁海文国家实验室);Princeton Center for Theoretical Science, Princeton University(普林斯顿大学理论科学中心);Universidad Autónoma de Madrid(马德里自治大学)
Complete two-loop Yukawa-induced running of the Higgs-gluon coupling in SMEFT
Karlsruhe Institute of Technology (KIT)(卡尔斯鲁厄理工学院);Università degli Studi di Padova(帕多瓦大学);Istituto Nazionale di Fisica Nucleare, Sezione di Padova(意大利国家核物理研究所帕多瓦分部)
There are two canonical approaches to treating the Standard Model as an Effective Field Theory (EFT): Standard Model EFT (SMEFT), expressed in the electroweak symmetric phase utilizing the Higgs doublet, and Higgs EFT (HEFT), expressed in the broken phase utilizing the physical Higgs boson and an independent set of Goldstone bosons. HEFT encompasses SMEFT, so understanding whether SMEFT is sufficient motivates identifying UV theories that require HEFT as their low energy limit. This distinction is complicated by field redefinitions that obscure the naive differences between the two EFTs. By re…
We study the production of Higgs bosons at high transverse momenta via vector-boson fusion (VBF) in the Standard Model Effective Field Theory (SMEFT). We find that contributions from four independent operator combinations dominate in this limit. These are the same `high energy primaries' that control high energy diboson processes, including Higgs-strahlung. We perform detailed collider simulations for the diphoton decay mode of the Higgs boson as well as the three final states arising from the ditau channel. Using the quadratic growth of the SMEFT contributions relative to the Standard Model (…
The study of Higgs boson production at large transverse momentum is one of the new frontiers for the LHC Higgs physics programme. This paper considers boosted Higgs production in the Standard Model Effective Field Theory (SMEFT). We focus on the gluon fusion and $t{\bar t}H$ production processes and study the effects of three dimension-6 operators: the top Yukawa operator, the gluon-Higgs effective coupling and the chromomagnetic dipole operator of the top quark. We perform a detailed study of the sensitivity of current and future LHC data to the corresponding Wilson coefficients, consistently…
Matching HEFT and SMEFT in double and triple Higgs production from weak boson fusion
IFT-UAM/CSIC, Universidad Autónoma de Madrid(马德里自治大学);IFLP, CONICET - Dpto. de Física, Universidad Nacional de La Plata(拉普拉塔国立大学);IPARCOS, Universidad Complutense de Madrid(马德里康普顿斯大学)
We present a global analysis of the Higgs and electroweak sector, in the SMEFT framework and matched to a UV-completion. As the UV-model we use the triplet extension of the electroweak gauge sector. The matching is performed at one loop, employing functional methods. In the SFitter analysis, we pay particular attention to theory uncertainties arising from the matching. Our results highlight the complementarity between SMEFT and model-specific analyses.
Universidad de Granada(格拉纳达大学);Florida State University(佛罗里达州立大学);Universitat d’Alacant(阿利坎特大学);University of Manchester(曼彻斯特大学);INFN, Sezione di Roma(罗马国家核物理研究所)
Higgs boson pair production in SMEFT: shape and truncation studies
Karlsruhe Institute of Technology (KIT)(卡尔斯鲁厄理工学院);Radboud University Nijmegen(奈梅亨拉德堡德大学);Università di Padova(帕多瓦大学);Istituto Nazionale di Fisica Nucleare, Sezione di Padova(意大利国家核物理研究所帕多瓦分部)
Electroweak interactions assign a central role to the gauge group $SU(2)_L \times U(1)_Y$, which is either realized linearly (SMEFT) or nonlinearly (e.g., HEFT) in the effective theory obtained when new physics above the electroweak scale is integrated out. Although the discovery of the Higgs boson has made SMEFT the default assumption, nonlinear realization remains possible. The two can be distinguished through their predictions for the size of certain low-energy dimension-6 four-fermion operators: for these, HEFT predicts $O(1)$ couplings, while in SMEFT they are suppressed by a factor $v^2/…
We explore the interplay of New Physics (NP) effects in $(g-2)_\ell$ and $h \to \ell^+ \ell^-$ within the Standard Model Effective Field Theory (SMEFT) framework, including one-loop Renormalization Group (RG) evolution of the Wilson coefficients as well as matching to the observables below the electroweak symmetry breaking scale. We include both the leading dimension six chirality flipping operators including a Higgs and $SU(2)_L$ gauge bosons as well as four-fermion scalar and tensor operators, forming a closed operator set under the SMEFT RG equations. We compare present and future experimen…
The modern viewpoint is that the Standard Model is the leading part of an effective field theory that obeys the symmetry $SU(3)_C \times SU(2)_L \times U(1)_Y$. Since the discovery of the Higgs boson, it is generally assumed that this symmetry is realized linearly (SMEFT), but a nonlinear realization (e.g., HEFT) is still possible. The two differ in their predictions for the size of certain low-energy dimension-6 four-fermion operators: for these, HEFT allows $O(1)$ couplings, while in SMEFT they are suppressed by a factor $v^2/Λ_{\rm NP}^2$, where $v$ is the Higgs vev. In this talk, I argue t…
Constraining four-heavy-quark operators with top-quark, Higgs, and electroweak precision data
Karlsruhe Institute of Technology (KIT)(卡尔斯鲁厄理工学院);University of Manchester(曼彻斯特大学);Università di Padova(帕多瓦大学);Istituto Nazionale di Fisica Nucleare, Sezione di Padova(意大利国家核物理研究所帕多瓦分部)
More accurate $σ(\mathcal{G} \,\mathcal{G}\rightarrow h)$, $Γ(h \rightarrow \mathcal{G} \,\mathcal{G}, \mathcal{A} \mathcal{A}, \barΨ Ψ)$ and Higgs width results via the geoSMEFT