Related papers: Probing Left-Right Seesaw using Beam Polarization …
Numerous non-standard dynamics are described by contact-like effective interactions that can manifest themselves in electron-positron collisions only through deviations of the observables (cross sections, asymmetries) from the Standard…
We study potential contribution of the heavy right-handed neutrino exchange in the process $e^{+}e^{-} \rightarrow W^{+}W^{-}$. This process is sensitive to heavy neutrinos with masses larger than $\sqrt{s}$. The Monte Carlo simulation of…
Through the simultaneous measurement of the transverse size as a function of longitudinal position, and the longitudinal distribution of luminosity, we are able to measure the $\beta_y^\ast$ (vertical envelope function at the collision…
The MEG experiment makes use of one of the world's most intense low energy muon beams, in order to search for the lepton flavour violating process $\mu^{+} \rightarrow {\rm e}^{+} \gamma$. We determined the residual beam polarization at the…
The breaking of parity, a fundamental symmetry between left and right is best understood in the framework of left-right symmetric extension of the standard model. We show that the production of a heavy right-handed neutrino at the proposed…
It is shown that if electron and positron beams at a linear collider are transversely polarized, azimuthal asymmetries of the final-state top quark in e+e- --> t tbar can be used to probe a combination of couplings of left and right…
We consider the nu_mu to nu_e oscillation measurements that would be possible at upgraded 1 GeV and multi-GeV conventional neutrino sources driven by future megawatt-scale proton drivers. If these neutrino superbeams are used together with…
Contactlike nonstandard interactions can be revealed only through deviations of observables from the standard model predictions. We consider a number of such nonstandard scenarios, and discuss their identification as sources of deviations…
Probing the origin of neutrino mass by disentangling the seesaw mechanism is one of the central issues of particle physics. We address it in the minimal left-right symmetric model and show how the knowledge of light and heavy neutrino…
We consider the corrections that arise at one loop when integrating out heavy fields in supersymmetric models. We show that, in type-I see-saw models, complex A and B terms of the heavy right-handed neutrino give radiative contributions to…
We study the impact of beam polarization on radiative neutralino production e+e- \to \chi^0_1 \chi^0_1 photon at the International Linear Collider. We show that longitudinal polarized beams significantly enhance the signal and…
We study electron-electron contact-interaction searches in the process e^+e^-\to e^+e^- at a future e^+e^- Linear Collider with both beams longitudinally polarized. We evaluate the model-independent constraints on the coupling constants,…
Left-right symmetric models (LRSM) were proposed to reconcile the apparent parity violation in weak interactions with our intrinsic notion of fundamental parity symmetry. It was quickly realized that LRSM offers a viable framework for…
We investigate the charged scalar lepton production processes $\gamma\gamma\to{\widetilde{\ell}}^{+}{\widetilde{\ell}}^{-}$ at high energy $\gamma\gamma$ colliders in the framework of the minimal supersymmetric standard model (MSSM). Here…
Polarized lepton beams are an important aspect in the design of the future 100 km-scale Circular Electron-Positron Collider (CEPC). Precision beam energy calibration using resonant depolarization, as well as longitudinally polarized…
Polarized neutrons are a powerful probe to investigate magnetism in condensed matter on length scales from single atomic distances to micrometers. With the ongoing advancement of neutron optics, that allow to transport beams with increased…
The energy spectra of the lepton(s) in eebar --> ttbar --> l^{+-}X/ l^+l^- X' at next linear colliders (NLC) are analyzed a model-independent way for arbitrary longitudinal beam polarizations as a general test of possible anomalous…
We discuss the potential of NLC500 and NLC1000 to probe Z-Z' mixing and mass by the reaction e^+e^- -> W^+W^- with longitudinally polarized electrons. We perform a model-independent analysis of the deviations from the Standard Model, and…
In addition to the well established large atmospheric angle, a large solar angle is probably present in the leptonic sector. In the context of the see-saw and by means of a bottom-up approach, we explore which patterns for the Dirac and…
The discovery potential for detecting new heavy Majorana and Dirac neutrinos at some recently proposed high energy $e^+e^-$ colliders is discussed. These new particles are suggested by grand unified theories and superstring-inspired models.…