Related papers: Probing Contact Interactions at High Energy Lepton…
We explore the discovery and analysis potentials of the HERA collider, with and without polarized beams, in search for electron-quark contact interactions in the neutral current channel. We find that the sensitivity to contact interactions…
A search for new top quark interactions is performed within the framework of an effective field theory using the associated production of either one or two top quarks with a Z boson in multilepton final states. The data sample corresponds…
Cross sections, angular distributions and forward-backward asymmetries are presented, of two-fermion events produced in e+e- collisions at centre-of-mass energies from 189 to 209 GeV at LEP, measured with the ALEPH detector. Results for…
This Letter describes the search for an enhanced production rate of events with a charged lepton and a neutrino in high-energy pp collisions at the LHC. The analysis uses data collected with the CMS detector, with an integrated luminosity…
Recent results from searches for new physics at HERA are reviewed. Exploiting the uniqueness of lepton-hadron collisions at high energy, searches are performed for electron-quark resonant states (leptoquarks or squarks in R-parity-violating…
The charge asymmetry in top quark production at hadron colliders is sensitive to beyond-the-Standard-Model four-fermion interactions. In this study we compare the sensitivity of cross-section and charge asymmetry measurements to effective…
Results are reported from a search for the effects of contact interactions using events with a high-mass, oppositely charged muon pair. The events are collected in proton-proton collisions at sqrt(s) = 7 TeV using the Compact Muon Solenoid…
We investigate the sensitivity of a future 10 TeV muon collider to dimension-6 operators in the Standard Model Effective Field Theory (SMEFT), focusing on Higgs and top quark production processes. The analysis includes two-fermion and…
A search for physics beyond the Standard Model in neutral current deep inelastic scattering at high negative four-momentum transfer squared Q^2 is performed in e^{\pm}p collisions at HERA. The differential cross section ds/dQ^2, measured…
At high energies photon-photon interactions are dominated by quantum fluctuations of the photons into fermion-antifermion pairs and into vector mesons. This is called photon structure. Electron-positron collisions at LEP are an ideal…
A contact four-fermion interaction between light quarks and electrons has been evoked as a possible explanation for the excess of events observed by HERA at high-$Q^2$. We explore the 1-loop effects of such interaction in $\Gamma(Z^0 \to…
We investigate the Lepton Flavor Violating (LFV) process $e^{+}e^{-}\to e^{+}e^{-}e\mu$ ($e=e^-,\,e^+,\,\mu=\mu^-,\,\mu^+ $) at future circular colliders, probing the effective $\gamma\gamma e\mu$ interaction through photon fusion. Within…
For the first time the experiments ALEPH, DELPHI, L3 and OPAL have presented preliminary results for fermion-pair production in e+e- collisions on the full data set above the Z pole. A combined analysis of the Bhabha scattering measurements…
Multi-TeV muon colliders offer a powerful means of accessing new physics coupled to muons while generating clean and intense high-energy neutrino beams via muon decays. We study a fixed-target experiment leveraging the neutrino beams and a…
We summarize results of the 1996 Snowmass workshop on future prospects for discovering dynamical electroweak symmetry breaking, compositeness, and anomalous couplings of quarks at colliders. We present the mass reach of the Tevatron to a…
Meson-baryon systems with strangeness content provide a unique laboratory for investigating the strong interaction and testing theoretical models of hadron structure and dynamics. In this work, the measured correlation functions for…
The four fermion contact interactions, required to explain the anomalous HERA result, could come from the exchange of new heavy (probably composite) resonances. Depending on their charges and quantum numbers, one gets different scenarios…
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 Large Hadron Collider can do precision physics at a level that is competitive with electroweak precision constraints when probing physics beyond the Standard Model. We present a simple yet general parameterization of the effect of an…
The electric and magnetic dipole moments of the electron and of the muon provide stringent tests of the Standard Model and sensitive probes of new physics. By contrast, the corresponding dipole moments of the $\tau$ lepton remain weakly…