Related papers: Sensitivities of Prospective Future e+e- Colliders…
We consider the issue of the top quark Yukawa coupling measurement in a model in dependent and general case with the inclusion of CP-violation in the coupling. Arguably the best process to study this coupling is the associa ted production…
We update the global fit to electroweak precision observables, including the effect of the latest measurements at hadron colliders of the $W$ and top-quark masses and the effective leptonic weak mixing angle. We comment on the impact of…
We study standard electroweak/Higgs processes at the high-energy lepton colliders ILC and CLIC. We identify a subset of three operators in the SMEFT that give leading contributions to these processes at high energies. We then perform a…
New physics close to the electroweak scale is well motivated by a number of theoretical arguments. However, colliders, most notably the Large Hadron Collider (LHC), have failed to deliver evidence for physics beyond the Standard Model. One…
We treat the Standard Model as the low-energy limit of an effective field theory that incorporates higher-dimensional operators to capture the effects of decoupled new physics. We consider the constraints imposed on the coefficients of…
This document provides a writeup of all contributions to the workshop on "High precision measurements of $\alpha_s$: From LHC to FCC-ee" held at CERN, Oct. 12--13, 2015. The workshop explored in depth the latest developments on the…
We study the triple Higgs self-coupling at future $e^{+}e^{-}$ colliders energies, with the reactions $e^{+}e^{-}\to b \bar b HH$ and $e^{+}e^{-}\to t \bar t HH$. We evaluate the total cross section of $b\bar bHH$, $t\bar tHH$ and calculate…
We study the complementarity of the proposed multi-TeV muon colliders and the near-future gravitational wave (GW) detectors to the first order electroweak phase transition (FOEWPT), taking the real scalar extended Standard Model as the…
The neutral Higgs boson predicted from spontaneous breaking of electroweak symmetry in the standard model (SM) has been discovered. Precision test of the Higgs boson properties is one of the promising ways to study new physics beyond SM.…
The particle discovered in the Higgs boson searches at the LHC with a mass of about 125 GeV is compatible within the present uncertainties with the Higgs boson predicted in the Standard Model (SM), but it could also be identified with one…
After the discovery of the Higgs boson, several future experiments have been proposed to study the Higgs boson properties, including two circular lepton colliders, the CEPC and the FCC-ee, and one linear lepton collider, the ILC. We…
Pair-production and single-production of $W$ bosons provide many opportunities to look for new physics via precision measurements, for instance via scrutinising the involved triple-gauge vertices or by measuring CKM matrix elements in an…
The future circular $e^+ e^-$ collider (FCC-ee) stands out as the next flagship project in particle physics, dedicated to uncovering the microscopic origin of the Higgs boson. In this context, we assess indirect probes of the Minimal…
As we use the standard model effective field theory to search for signs of new physics beyond the direct reach of the LHC, we often wonder what we may learn from the effective field theory, and what it would look like to make a discovery…
We study the contributions of colorless vectorlike fermions to the triple gauge couplings $W^+ W^- \gamma$ and $W^+ W^- Z^0$. We consider models in which their coupling to the Standard Model Higgs boson is allowed or forbidden by quantum…
The aim of the future linear colliders is to extend the sensitivity to new physics beyond the reach of the LHC. Several models predict the existence of new vector resonances in the multi-TeV region. We review the existing limits on the…
At a prospective e+e- Linear Collider (LC) a very precise determination of the top quark mass with an accuracy of $\delta m_t <= 100 MeV$ will be possible. This is to be compared with the envisaged accuracy of $\delta m_t = 1-2 GeV$ at the…
We analyze lepton flavor violation (LFV) using the Standard Model Effective Field Theory (SMEFT) framework at the future lepton colliders. Our focus is on the associated production of tau lepton with electron/muon at the electron-positron…
For the processes e+e-\to \mu+\mu-, \tau+\tau-, b\bar{b} and c\bar{c} at a future e+e- collider with \sqrt{s}=0.5 TeV, we examine the sensitivity of the helicity cross sections to four-fermion contact interactions. If longitudinal…
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…