Related papers: Measuring the tau polarization at ILC
We show that transverse and normal single-$tau$ polarization of $tau$ pairs produced at $e^+$ $e^-$ unpolarized collisions, at the $Z$ peak, are sensitive to weak (magnetic and electric) dipole moments of the $tau$. We also show how these…
In a recent paper, eight semileptonic parameters were defined to specify the most general Lorentz-invariant spin correlation functions for tau semileptonic decays. The parameters were physically defined in terms of tau-decay partial-width…
The new proposals for high luminosity B/Flavor factories, near and on top of the $\Upsilon$ resonances, allow for a detailed investigation of CP-violation in the $\tau$-pair production. In particular, bounds on the tau electric dipole…
We review the current knowledge of the couplings of the tau lepton to the electroweak gauge bosons, the W, Z and photon, obtained from the full L3 data sample at center-of-mass energies near the Z mass. Measurements of the the effective…
Lepton flavor violation in the $\tau\mu$ sector would be a clear sign of Beyond Standard Model physics. We employ the SMEFT framework to study the process $e^+e^-\to\tau\mu$ at the ILC and CLIC. We find that the $e^+e^-$ beam polarizations…
We present a study of top quark polarization in $t \overline{t}$ events produced in $p \overline{p}$ collisions at $\sqrt{s}=1.96$ TeV. Data correspond to 9.7 fb$^{-1}$ collected with the D0 detector at the Tevatron. We use final states…
We investigate the sensitivity to new physics of the process e+e- -> t bar{t} when the top polarization is analyzed using leptonic final states e+e- -> t \bar{t} -> l+l- b \bar{b} nu_l \bar{nu}_l. We first show that the kinematical…
Measurements of polarized electron-nucleon scattering can be realized at the TESLA linear collider facility with projected luminosities that are about two orders of magnitude higher than those expected of other experiments at comparable…
We have investigated the electromagnetic moments of the tau lepton in $e^{+}e^{-} \rightarrow e^{+}\gamma^{*} \gamma^{*} e^{-}\rightarrow e^{+}\tau \bar{\tau}e^{-}$ process at the CLIC. We have obtained 95% confidence level bounds on the…
Measuring the tau-lepton ($\tau$) anomalous magnetic moment $a_\tau = (g_\tau -2)/2$ in photon fusion production ($\gamma\gamma\to\tau\tau$) tests foundational Standard Model principles. However, $\gamma\gamma\to\tau\tau$ eludes observation…
The methods to measure the polarization of the x-rays from highly charged heavy ions with a significantly higher accuracy than the existing technology is needed to explore relativistic and quantum electrodynamics (QED) effects including the…
Potential of the LHC to determine the electromagnetic couplings of the $\tau$ lepton is discussed via the process ${\gamma\gamma \to \tau^{+}\tau}^{-}$. Highly improved constraints of the anomalous magnetic and electric dipole moments have…
Results are presented for a test of the compositeness of the heaviest charged lepton, $\tau$, using data collected by the CMS experiment in proton-proton collisions at a center-of-mass energy of 13 TeV at the CERN LHC. The data were…
A concept to measure the neutron electric charge is presented which employs a precision Talbot-Lau interferometer in a high-intensity pulsed neutron beam. It is demonstrated that the sensitivity for a neutron charge measurement can be…
We investigate the potential of the ILC for measuring anomalous quartic gauge couplings, both in production of three electroweak gauge bosons as well as in vector boson scattering. Any new physics that could possibly couple to the…
The nucleon energy-energy correlator (NEEC) was proposed in 2209.02080 as a new way of studying nucleon intrinsic dynamics. In this work, we present a detailed derivation of the factorization theorem that enables the measurement of the…
The introduction of a longitudinal polarised positron beam in an $e^+e^-$ linear collider calls for its polarisation monitoring and measurement at low energies near its production location. Here it is shown that a relatively simple Bhabha…
The FCC-ee aims to improve on electroweak precision measurements, with goals of 100 keV on the Z mass and width, and a fraction of MeV on the W mass. Compared to LEP, this implies a much improved knowledge of the centre-of-mass energy when…
Precise measurements of magnetic and electric dipole moments are important tests of the Standard Model and beyond Standard Model physics, particularly for the electron and the muon. However, the situation presents distinctive challenges…
The first measurement of the polarization of charm baryons by the LHCb experiment recorded in fixed-target mode is presented. The polarization of $\Lambda_c$ baryons is studied in collisions of protons, at an energy of 2.51 TeV, incident on…