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Related papers: Tau Physics with Polarized Beams

200 papers

We report a measurement of the magnitude of the tau neutrino helicity from tau-pair events taken with the CLEO detector at the CESR electron-positron storage ring. Events in which each tau undergoes the decay tau -> h nu, with h a charged…

High Energy Physics - Experiment · Physics 2010-04-08 T. Coan , CLEO Collaboration

We study the longitudinal, transverse, and normal polarization components of the tau lepton in the decays $\bar{B}^0 \to D^{(\ast)} \tau^- \bar\nu_{\tau}$ and discuss their role in searching for new physics (NP) beyond the standard model…

High Energy Physics - Phenomenology · Physics 2017-03-08 Mikhail A. Ivanov , Jürgen G. Körner , Chien-Thang Tran

The polarisation of $\tau$'s produced in Z decay is measured using 160 pb$^{-1}$ of data accumulated at LEP by the ALEPH detector between 1990 and 1995. The variation of the polarisation with polar angle yields the two parameters ${\cal…

High Energy Physics - Experiment · Physics 2012-08-27 ALEPH Collaboration

This paper describes a measurement of the Michel parameters, \eta, \rho, \xi, \xi\delta, and the average \nu_{\tau} helicity, h_{\nu_{\tau}}, in tau lepton decays together with the first measurement of the tensor coupling in the weak…

High Energy Physics - Experiment · Physics 2010-05-28 The DELPHI Collaboration , P. Abreu

We study the polarization vector of $\tau^-$ ($\tau^+$) leptons created in $\nu_\tau$ ($\bar{\nu}_\tau$) - Nucleon deep inelastic scattering. Our work is oriented toward ultra-high energy particles relevant for cosmic-rays experiments. The…

High Energy Physics - Phenomenology · Physics 2008-07-09 Kévin Payet

The basic parameters of supersymmetric theories can be determined at future e^+e^- linear colliders with high precision. We investigate in this report how polarisation measurements in \tilde{\tau} and \tilde{t} or \tilde{b} decays to \tau…

High Energy Physics - Phenomenology · Physics 2011-01-27 E. Boos , H. -U. Martyn , G. Moortgat-Pick , M. Sachwitz , A. Sherstnev , P. M. Zerwas

The $\tau$ lepton arising from the scalar tau ($\st$) decay is naturally polarized. $\ptau$ depends on the left--right mixing of the $\st$ and the gaugino--higgsino mixing of the neutralino. The polarization $\ptau$ could be measured from…

High Energy Physics - Phenomenology · Physics 2009-10-28 Mihoko M. Nojiri

The meson decays $B\to D\tau\nu$ and $B\to D^* \tau \nu$ are sensitive probes of the $b\to c\tau\nu$ transition. In this work we present a complete framework to obtain the maximum information on the physics of $B\to D^{(*)}\tau\nu$ with…

High Energy Physics - Phenomenology · Physics 2020-12-30 Pouya Asadi , Anna Hallin , Jorge Martin Camalich , David Shih , Susanne Westhoff

Energy and angular distributions of the tau decay products in the CERN-to-Gran Sasso $\nu_\tau$ appearance experiments are studied for the decay modes $\tau\to\pi\nu$ and $\tau\to l\bar\nu\nu$ (l=e or mu). We find that the decay particle…

High Energy Physics - Phenomenology · Physics 2009-11-11 Mayumi Aoki , Kaoru Hagiwara , Kentarou Mawatari , Hiroshi Yokoya

We present here the major results obtained in $\tau$ physics by the Belle and Belle II experiments. For the Belle II experiment, we also discuss prospects for improved measurements of the $\tau$ lepton properties, new results in Michel…

High Energy Physics - Experiment · Physics 2024-05-28 Denis Bodrov

In this paper a general method to measure the longitudinal polarization of $\tau$ lepton in the process $pp \rightarrow Z^{0} \rightarrow \tau\tau$ is described. The method of optimal observable allows to distinguish between the $\tau$…

High Energy Physics - Phenomenology · Physics 2018-05-29 Vladimir Cherepanov , Wolfgang Lohmann

The Michel parameters of the leptonic tau decays are measured using the OPAL detector at LEP. The Michel parameters are extracted from the energy spectra of the charged decay leptons and from their energy-energy correlations. A new method…

High Energy Physics - Experiment · Physics 2008-11-26 The OPAL Collaboration , K. Ackerstaff et al

The process $e^- e^+ \to \tau^- \tau^+$ is of particular interest because the tau lepton polarisation can be reconstructed, allowing its chiral nature to be probed. This note reports on a study of the reconstruction of the di-tau final…

High Energy Physics - Experiment · Physics 2020-02-18 Daniel Jeans , Keita Yumino

This paper provides a detailed description of the method for the first direct measurement of all Michel parameters in the $\tau^- \to \mu^- \bar{\nu}_\mu\nu_\tau$ decay related to the polarization of the daughter muon. An application of the…

High Energy Physics - Phenomenology · Physics 2022-10-11 D. Bodrov , P. Pakhlov

For the 1994/95 run of the SLD experiment at SLAC, a Compton polarimeter measured the luminosity-weighted electron beam polarization to be (77.2 +- 0.5)%. This excellent accuracy is achieved by measuring the rate asymmetry of…

High Energy Physics - Experiment · Physics 2007-05-23 M. Woods , representing the SLD collaboration

The prospects for the analysis of tau channels at the SUSY benchmark point SPS1a', especially from e+e- -> stau_1 stau_1 and e+e- -> stau_2 stau_2, have been studied in full simulation of the ILD detector concept forseen for the…

High Energy Physics - Experiment · Physics 2015-03-13 Philip Bechtle , Mikael Berggren , Jenny List , Peter Schade , Olga Stempel

We study the spin polarizations of both tau leptons in the decay b -> s tau+ tau-. In addition to the polarization asymmetries involving a single tau, we construct asymmetries for the case where both polarizations are simultaneously…

High Energy Physics - Phenomenology · Physics 2009-11-07 Wafia Bensalam , David London , Nita Sinha , Rahul Sinha

Kinematics restrict the ability of rare charm decays to explore the charged Lepton Flavor Violation processes mediated by the quark-level $c\to u \ell \tau$ transition. To fill the gap, we propose exploring new physics (NP) through the…

High Energy Physics - Phenomenology · Physics 2024-04-09 Xin-Shuai Yan , Liang-Hui Zhang , Qin Chang , Ya-Dong Yang

Relativistic heavy-ion beams at the LHC are accompanied by a large flux of equivalent photons, leading to multiple photon-induced processes. This proceeding presents searches for physics beyond the Standard Model enabled by photon-photon…

High Energy Physics - Experiment · Physics 2023-07-17 Klaudia Maj

Certain CP-odd momentum correlations in the production and subsequent decay of $\tau$ pairs in $e^+ e^-$ collisions are enhanced significantly when the $e^+$ and $e^-$ beams are longitudinally polarized. These may be used to probe the real…

High Energy Physics - Phenomenology · Physics 2009-12-30 B. Ananthanarayan , Saurabh D. Rindani