Related papers: Precision $\mu^+\mu^+$ and $\mu^+e^-$ elastic scat…
We discuss the capabilities of future muon colliders to resolve important particle physics questions. A collider with c.m. energy $\sqrt s = 100$ to 500~GeV offers the unique opportunity to produce Higgs bosons in the $s$-channel and…
Measurements of the cross section for $\bar \nu_e e^-$ elastic scattering with unprecedented precision have recently been proposed. The impact of these experiments for detecting possible deviations from the standard electroweak theory is…
We describe the physics potential of $e^+e^-$ linear colliders in this report. These machines are planned to operate in the first phase at a center-of --mass energy of 500 GeV, before being scaled up to about 1 TeV. In the second phase of…
We summarize the potential of muon colliders to probe fundamental physics. $W^+W^-$, \bar tt, and $Zh$ threshold measurements could determine masses to precisions $\Delta M_W = 6$ MeV, $\Delta m_t = 70$ MeV, and $\Delta m_h = 45$ MeV, to…
Future high energy linear electron positron colliders with centre-of-mass enegies between 90 and 1000 GeV offer a unique opportunity to study precisely the Standard Model and phenomena from new physics. Most important, the mechanism of…
Extending earlier investigations, we analyze the quasi-elastic scattering of strongly interacting electroweak bosons at high-energy e+-e- colliders. The three processes e+e- -> bar-nu nu W+W-, bar-nu nu ZZ, and e-e- -> W-W- are examined at…
The ultra-cold muon technology developed for the muon $g-2$ experiment at J-PARC provides a low emittance $\mu^+$ beam which can be accelerated and used for realistic collider experiments. We consider the possibility of new collider…
Future lepton colliders, such as those based on linear $e^+e^-$ or circular $\mu^+\mu^-$ accelerators, are expected to attain centre-of-mass energies in the multi-TeV range. In this regime the impact of QED and of weak radiation, in both…
We discuss the experimental and theoretical uncertainties on precision electroweak observables and their relationship to the indirect constraints on the Higgs-boson mass, $\MH$, in the Standard Model (SM). The critical experimental…
Precise determinations of the masses of the $W$ boson and of the top quark could stringently test the radiative structure of the Standard Model (SM) or provide evidence for new physics. We analyze the excellent prospects at a muon collider…
Muon colliders are an exciting possibility for reaching the highest energies possible on the shortest timescale. They potentially combine the greatest strengths of $e^+e^-$ and $pp$ colliders by bridging the energy versus precision…
We investigate what can be learned at a linear collider about the sector of electroweak symmetry breaking from a precise measurement of the Higgs boson production cross section through the process e+e- -> hZ. We focus on deviations from the…
Muon colliders offer the possibility to go to very high energies with relatively small circular colliders, energies up to 10 or 14 TeV are envisioned. Due to their very clean collider environment they provide a fantastic tool to search for…
We perform a detailed study of the process $e^+e^-\to \mu^+\mu^-\nu_l\bar\nu_l$ including all contributions. The contributions other than from real gauge boson production leads to a rich phenomenology. We explore the use of the process as a…
We perform a complete simulation of the process $ e^+ e^- \to \tau^+ \tau^- \nu \bar{\nu}$, where $\nu$ can be an electron, muon or tau neutrino, in the context of a general Higgs coupling to $\tau$ leptons. We analyse various kinematical…
A comprehensive review of physics at an e+e- Linear Collider in the energy range of sqrt{s}=92 GeV--3 TeV is presented in view of recent and expected LHC results, experiments from low energy as well as astroparticle physics.The report…
Muon colliders offer special opportunities to discover and study new physics. With the high intensity source of muons at the front end, orders of magnitude improvements would be realized in searches for rare muon processes, in deep…
The last years have seen a great development in our understanding of particle physics at the weak scale. Precision electroweak observables have played a key role in this process and their values are consistent, within the Standard Model…
The search and study of heavy Higgs bosons is an important part of the anticipated physics program of a high energy e+e- linear collider. This paper reviews the expected sensitivity of e+e- collisions from 0.5 up to 3 TeV in the study of…
Methods for measuring the absolute center-of-mass energy, $\sqrt{s}$, and its distribution, are investigated for future $e^+e^-$ Higgs-factory colliders using in situ $e^+e^-$ collisions. We emphasize the potential of an estimator based on…