Related papers: Potential Blind Directions at TeraZ
We discuss the impact of many previously neglected effects of higher dimensional operators when fitting to Electroweak Precision data (EWPD) in the Standard Model Effective Field Theory (SMEFT). We calculate the general case of $2…
The Fermi effective theory of the weak interaction helped identify the structure of the electroweak sector of the Standard Model, and the chiral effective Lagrangian pointed towards QCD as the theory of the strong interactions. The Standard…
We calculate the one- and two-loop matching corrections in the Standard Model effective field theory (SMEFT) that impact electroweak precision measurements and flavour physics observables, focusing on the contributions of third-generation…
We study the potential of future Electron-Ion Collider (EIC) data to probe four-fermion operators in the Standard Model Effective Field Theory (SMEFT). The ability to perform measurements with both polarized electron and proton beams at the…
We study angular observables in the $e^+e^-\to Z H\to \ell^+ \ell^-\,b\bar{b}$ channel at future circular $e^+ e^-$ colliders such as CEPC and FCC-ee. Taking into account the impact of realistic cut acceptance and detector effects, we…
Testing the idea of naturalness is and will continue to be one of the most important goals of high energy physics experiments. It will play a central role in the physics program of future colliders. In this paper, we present projections of…
In the Standard Model (SM), electroweak (EW) corrections become significant at high energies, particularly at the tera-electronvolt scale and beyond, due to the presence of Sudakov logarithms. At these energy scales, the Standard Model…
The physics case for electron-positron beams at the Future Circular Collider (FCC-ee) is succinctly summarized. The FCC-ee core program involves $e^+e^-$ collisions at $\sqrt{s}$ = 90, 160, 240, and 350 GeV with multi-ab$^{-1}$ integrated…
The current projected sensitivity on the electromagnetic coupling $\alpha_\textit{em}(m_Z^2)$ represents a bottleneck for the precision electroweak program at FCC-ee. We propose a novel methodology to extract this coupling directly from…
We report the design status and beam dynamics challenges for the electron-positron branch of the Future Circular Collider (FCC) study, as of August 2015. After recalling motivation and physics requirements for the FCC-ee, we briefly discuss…
With no direct evidence for new physics at the TeV scale, deviations from the Standard Model (SM) can be explored systematically through Effective Field Theories (EFTs) such as the Standard Model EFT (SMEFT). SMEFT extends the SM by…
The use of resonant depolarization has been suggested for precise beam energy measurements (better than 100 keV) in the $e^{+}e^{-}$ Future Circular Collider (FCC-$e^{+}e^{-}$) for Z and WW physics at 45 and 80 GeV beam energy respectively.…
The current status of electroweak precision observables in the Minimal Supersymmetric Standard Model (MSSM) is reviewed. We focus in particular on the $W$ boson mass, M_W, the effective leptonic weak mixing angle, sin^2 theta_eff, the…
The discovery of neutrino oscillations and masses provides strong motivation to extend the Standard Model by including right-handed neutrinos, which lead to heavy neutrino states that could exist at the electroweak scale. These states may…
This note presents constraints on Standard Model parameters using published and preliminary precision electroweak results measured at the electron-positron colliders LEP and SLC. The results are compared with precise electroweak…
There have been a great deal of works on the precision test of the standard model (SM) because of the incredibly precise data obtained at the LEP and the new measurements of $M_W$ and $m_t$ at the Fermilab Tevatron as well as the recent…
We study the electromagnetic form factors of electrically neutral dark-sector particles in this paper. Concretely speaking, we focus on operators that can lead to interactions of fermionic dark states with the Standard-Model (SM) photon,…
This manuscript is devoted to the description of the proposed Future Circular Collider (FCC) project and its physics program focused on measurements involving heavy quarks. It summarizes the report submitted to the US 2021 Snowmass Process…
We investigate how extensions of the Standard Model (SM) involving heavy neutral leptons (HNLs) can be probed at FCC-ee, the proposed high-energy circular $e^+e^-$ collider. Using the effective field theory (EFT) approach, we determine the…
There have been several important recent developments in precision electroweak tests. These include: the new LEP energy scan during the 1993 run; the first high-precision results on the left-right asymmetry from the SLD Collaboration at…