Related papers: Weak Neutral Current Studies with Positrons
Several models of neutrino masses predict the existence of neutral heavy leptons. Here, we review current constraints on heavy neutrinos and apply a new formalism separating new physics from Standard Model. We discuss also the indirect…
We present a phenomenological study of nuclear effects in neutrino charged-current interactions, using transverse kinematic imbalances in exclusive measurements. Novel observables with minimal dependence on neutrino energy are proposed to…
Precision probes of new physics are often interpreted through their indirect sensitivity to short-distance scales. In this proceedings contribution, we focus on the question of which precision observables, at current sensitivity levels,…
Light neutral mediators, with mass $\lesssim 1$ GeV, are common features of extensions to the Standard Model (SM). Current astrophysical and terrestrial experiments have constrained the model parameter space, and planned experiments around…
As an unstable light pure leptonic system, positronium is a very specific probe atom to test bound state QED. In contrast to ordinary QED for free leptons, the bound state QED theory is not so well understood and bound state approaches…
A weakly coupled new neutral gauge boson forms a narrow resonance that is hard to discover directly in e+e- collisions. However, if the gauge boson mass is below the center-of-mass energy, it can be produced through processes where the…
The consideration is presented of possible neutron experiments to search for new short-range spin-dependent forces. The spin-dependent nucleon-nucleon interaction between neutron and nuclei may cause different effects: phase shift of a…
The intense muon beams which will be available at a neutrino factory provide a unique opportunity for searching for physics beyond the standard model, both in lepton flavor violation and in the search for a permanent electric dipole moment…
In high centre-of-mass energy lepton-nucleon collisions the space-time time resolution of partonic processes can be {\it fine-tuned} within a dynamical range which is unattainable in hadronic collisions. Replacing nucleons by nuclei of…
The discovery of a new neutral gauge boson, $Z'$, could provide the first concrete evidence of physics beyond the standard model. We explore how nuclear weak charge measurements in atomic parity violation (APV) experiments can be used to…
New neutrino states \nu_b, sterile under the Standard Model interactions, can be coupled to baryons via the isoscalar vector currents that are much stronger than the Standard Model weak interactions. If some fraction of solar neutrinos…
The results of high precision weak neutral current (WNC), Z-pole, and high energy collider electroweak experiments have been the primary prediction and test of electroweak unification. The electroweak program is briefly reviewed from a…
Neutral and charged current deep inelastic ep scattering with longitudinally polarised lepton beams has been studied with the H1 and ZEUS detectors at HERA. The differential cross sections were measured in the range of four-momentum…
The future high-energy muon colliders, featuring both high energy and low background, could play a critical role in our searches for new physics. The smallness of neutrino mass is a puzzle of particle physics. Broad classes of solutions to…
Flavour-changing neutral currents are extremely rare processes in the standard model that can be sensitive to various new physics effects. The summary of the latest experimental results from the LHC experiments is given. Preliminary results…
The pure leptonic or semileptonic character of tau decays makes them a good laboratory to test the structure of the weak currents and the universality of their couplings to the gauge bosons. The hadronic $\tau$ decay modes constitute an…
High energy beams incident on a fixed target may scatter against atomic electrons. To a first approximation, one can treat these electrons as at rest. For precision experiments, however, it is important to be able to estimate the size of,…
The 6He nucleus is an ideal candidate to study the weak interaction. To this end we have built a high-intensity source of 6He delivering ~10^10 atoms/s to experiments. Taking full advantage of that available intensity we have performed a…
Results of a detailed study of strange particle production in neutrino neutral current interactions are presented using the data from the NOMAD experiment. Integral yields of neutral strange particles (K0s, Lambda, Lambda-bar) have been…
Nuclear physics tests of parity- and time-reversal invariance have both shaped the development of the Standard Model and provided key tests of its predictions. These studies now provide vital input in the search for physics beyond the…