267 citations · 3.2k across the 56 of their papers we have counts for
55 papers · 1 filter
Probing Top-quark Operators with Precision Electroweak Measurements
Yiming Liu, Yuhao Wang, Cen Zhang +2
In the Standard Model Effective Field Theory (SMEFT), operators involving the top quark are generally difficult to probe, and can generate sizable loop contributions to the electro…
Moments for positivity: using Drell-Yan data to test positivity bounds and reverse-engineer new physics
Xu Li, Ken Mimasu, Kimiko Yamashita +3
Moments of the leptonic angular distribution in the Drell-Yan process have recently been shown to be sensitive probes of a specific class of dimension-8, four-fermion operators in…
Truncation, validity, uncertainties
Ilaria Brivio, Sally Dawson, Jorge de Blas +19
The truncation of the standard-model effective field theory, its validity and the associated uncertainties have been discussed in meetings of the LHC EFT WG. Proposals were made by…
SMEFTs living on the edge: determining the UV theories from positivity and extremality
Cen Zhang
We study the "inverse problem" in the context of the Standard Model Effective Field Theory (SMEFT): how and to what extend can one reconstruct the UV theory, given the measured val…
Combined SMEFT interpretation of Higgs, diboson, and top quark data from the LHC
Jacob J. Ethier, Giacomo Magni, Fabio Maltoni +6
We present a global interpretation of Higgs, diboson, and top quark production and decay measurements from the LHC in the framework of the Standard Model Effective Field Theory (SM…
Positivity in Multi-Field EFTs
Xu Li, Hao Xu, Chengjie Yang +2
We discuss the general method for obtaining full positivity bounds on multi-field effective field theories (EFTs). While the leading order forward positivity bounds are commonly de…
Unambiguously Testing Positivity at Lepton Colliders
Jiayin Gu, Lian-Tao Wang, Cen Zhang
The diphoton channel at lepton colliders, , has a remarkable feature that the leading new physics contribution comes only from dimension-eight operators. Th…
Elastic positivity vs extremal positivity bounds in SMEFT: a case study in transversal electroweak gauge-boson scatterings
Kimiko Yamashita, Cen Zhang, Shuang-Yong Zhou
The positivity bounds, derived from the axiomatic principles of quantum field theory (QFT), constrain the signs of Wilson coefficients and their linear combinations in the Standard…
Positivity in electron-positron scattering: testing the axiomatic quantum field theory principles and probing the existence of UV states
Benjamin Fuks, Yiming Liu, Cen Zhang +1
We consider the positivity bounds on dimension-8 four-electron operators and study two related phenomenological aspects at future lepton colliders. First, if positivity is violated…
Automated one-loop computations in the SMEFT
Céline Degrande, Gauthier Durieux, Fabio Maltoni +3
We present the automation of one-loop computations in the standard-model effective field theory at dimension six. Our general implementation, dubbed SMEFT@NLO, covers all types of…
Convex Geometry Perspective to the (Standard Model) Effective Field Theory Space
Cen Zhang, Shuang-Yong Zhou
We present a convex geometry perspective to the Effective Field Theory (EFT) parameter space. We show that the second derivatives of the forward EFT amplitudes form a convex co…
Generalized positivity bounds on chiral perturbation theory
Yu-Jia Wang, Feng-Kun Guo, Cen Zhang +1
Recently, a new set of positivity bounds with derivatives have been discovered. We explore the generic features of these generalized positivity bounds with loop amplitudes and…
O new physics, where art thou? A global search in the top sector
I. Brivio, S. Bruggisser, F. Maltoni +5
We provide a comprehensive global analysis of Run II top measurements at the LHC in terms of dimension-6 operators. A distinctive feature of the top sector as compared to the Higgs…
Proposal for the validation of Monte Carlo implementations of the standard model effective field theory
Gauthier Durieux, Ilaria Brivio, Fabio Maltoni +38
We propose a procedure to cross-validate Monte Carlo implementations of the standard model effective field theory. It is based on the numerical comparison of squared amplitudes com…
Positivity constraints on aQGC: carving out the physical parameter space
Qi Bi, Cen Zhang, Shuang-Yong Zhou
Searching for deviations in quartic gauge boson couplings (QGCs) is one of the main goals of the electroweak program at the LHC. We consider positivity bounds adapted to the Standa…
A Monte Carlo global analysis of the Standard Model Effective Field Theory: the top quark sector
Nathan P. Hartland, Fabio Maltoni, Emanuele R. Nocera +4
We present a novel framework for carrying out global analyses of the Standard Model Effective Field Theory (SMEFT) at dimension-six: SMEFiT. This approach is based on the Monte Car…
Learning to pinpoint effective operators at the LHC: a study of the signature
Jorgen D'Hondt, Alberto Mariotti, Ken Mimasu +2
In the context of the Standard Model effective field theory (SMEFT), we study the LHC sensitivity to four fermion operators involving heavy quarks by employing cross section measur…
Probing top-quark couplings indirectly at Higgs factories
Gauthier Durieux, Jiayin Gu, Eleni Vryonidou +1
We perform a global effective-field-theory analysis to assess the combined precision on Higgs couplings, triple gauge-boson couplings, and top-quark couplings, at future circular $…
Positivity bounds on vector boson scattering at the LHC
Cen Zhang, Shuang-Yong Zhou
Weak vector boson scattering (VBS) is a sensitive probe of new physics effects in the electroweak symmetry breaking. Currently, experimental results at the LHC are interpreted in t…
Global and optimal probes for the top-quark effective field theory at future lepton colliders
Gauthier Durieux, Martín Perelló, Marcel Vos +1
We study the sensitivity to physics beyond the standard model of precise top-quark pair production measurements at future lepton colliders. A global effective-field-theory approach…
Learning to pinpoint effective operators at the LHC: a study of the signature
Jorgen D'Hondt, Alberto Mariotti, Ken Mimasu +2
In the context of the Standard Model effective field theory (SMEFT), we study the LHC sensitivity to four fermion operators involving heavy quarks by employing cross section measur…
Single-top associated production with a or boson at the LHC: the SMEFT interpretation
Celine Degrande, Fabio Maltoni, Ken Mimasu +2
At the LHC, top quarks can be produced singly with a sizeable rate via electroweak interactions. This process probes a limited set of top-quark electroweak couplings, i.e. , the sa…
Dimension-six electroweak top-loop effects in Higgs production and decay
Eleni Vryonidou, Cen Zhang
We study the next-to-leading order electroweak corrections to Higgs processes from dimension-six top-quark operators in the Standard Model Effective Field Theory approach. We consi…
Top Quark Properties
Cen Zhang
Recently, experimental collaborations have reported upper limits on the signal strength of four-top production at the LHC, which already leads to competitive cons…