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Related papers: Tau-Universality Violation with Light Neutralinos

200 papers

We investigate flavour violating decays of the long-lived lightest slepton and the tau lepton in the coannihilation region of the Minimal Supersymmetric Standard Model with a Seesaw mechanism to generate neutrino masses. We consider a…

High Energy Physics - Phenomenology · Physics 2011-06-13 Satoru Kaneko , Hiroki Saito , Joe Sato , Takashi Shimomura , Oscar Vives , Masato Yamanaka

We discuss the lower limit on the mass of the neutralino $\chi$ that can be obtained by combining data from $e^+e^-$ annihilation at LEP and elsewhere with astrophysical and theoretical considerations. Loopholes in the purely experimental…

High Energy Physics - Phenomenology · Physics 2009-09-11 John Ellis , Toby Falk , Keith Olive , Michael Schmitt

Supersymmetric models with broken R-parity induced by lepton number violating terms provide a calculable framework for neutrino masses and mixings. Within models with bilinear R-parity breaking six new physical phases appear which are…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. Hirsch , T. Kernreiter , W. Porod

We discuss supersymmetric contributions to the electroweak precision measurements in the Minimal Supersymmetric Standard Model for two cases: the quark-lepton universality violation $\delta_{q\ell}$ in charged currents and the ratio…

High Energy Physics - Phenomenology · Physics 2009-10-28 Youichi Yamada , Kaoru Hagiwara , Seiji Matsumoto

We discuss the phenomenology of the lightest stop in models where R-parity is broken by bilinear superpotential terms. In this class of models we consider scenarios where the R-parity breaking two-body decay ~t_1->\tau^+b competes with the…

High Energy Physics - Phenomenology · Physics 2009-09-17 Diego Restrepo , Werner Porod , Jose W. F. Valle

In this work, we study the possible unparticle signatures through tau pair production e+e- -> tau+tau- process at the low energy particle factories. We take into account lepton flavor conserving (s-channel) and violating (t-channel)…

High Energy Physics - Phenomenology · Physics 2009-06-16 O. Cakir , K. O. Ozansoy

Here we update the predictions for lepton flavour violating tau and muon decays, $l_j \to l_i \gamma$, $l_j \to 3 l_i$, and $\mu-e$ conversion in nuclei. We work within a SUSY-seesaw context where the particle content of the Minimal…

High Energy Physics - Phenomenology · Physics 2007-10-23 E. Arganda , M. J. Herrero

A mechanism has been suggested recently to generate the neutrino mass out of a dimension-seven operator. This is expected to relieve the tension between the occurrence of a tiny neutrino mass and the observability of other physics effects…

High Energy Physics - Phenomenology · Physics 2010-12-24 Yi Liao , Guo-Zhu Ning , Lu Ren

We analyze the CP violation in the semileptonic | \Delta S|=1 tau-decays in supersymmetric extensions of the standard model (SM) with R parity violating term. We show that the CP asymmetry of tau-decay is enhanced significantly and the…

High Energy Physics - Phenomenology · Physics 2008-12-18 D. Delepine , G. Faisel , S. Khalil

We evaluate the model-dependent piece of O(alpha) long-distance radiative corrections to tau^- \to \pi^- \pi^0\nu_{\tau} decays by using a meson dominance model. We find that these corrections to the di-pion invariant mass spectrum are…

High Energy Physics - Phenomenology · Physics 2009-11-11 F. Flores-Baez , A. Flores-Tlalpa , G. Lopez Castro , G. Toledo Sanchez

Semileptonic decays provide an excellent environment for testing the Standard Model (SM). Violation of lepton universality would be a smoking gun for physics beyond the SM. Using semi-tauonic $B$ decays, LHCb finds a value of…

High Energy Physics - Experiment · Physics 2016-11-28 Suzanne Klaver

The possible transverse polarization of the $\tau$-lepton, which is $T$-odd and can be used to measure CP-violation, is estimated precisely in the radiative decay mode $B_c \to \tau \bar \nu_\tau \gamma$ with possible parameters for the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Chao-Hsi Chang , A. K. Giri , Rukmani Mohanta , Guo-Li Wang

The existence of R-parity in supersymmetric models can be naturally explained as being a discrete subgroup of gauged baryon minus lepton number (B-L). The most minimal supersymmetric B-L model triggers spontaneous R-parity violation, while…

High Energy Physics - Phenomenology · Physics 2014-08-06 Zachary Marshall , Burt A. Ovrut , Austin Purves , Sogee Spinner

We review world-average measurements of the tau lepton electroweak couplings, in both decay (including Michel parameters) and in production ($Z^0\to \tau^+\tau^-$ and $W^-\to\tau^-\nubar_\tau$). We review the searches for anomalous weak and…

High Energy Physics - Experiment · Physics 2007-05-23 Alan J. Weinstein

We present a new method to measure the transverse spin correlation in the $H\to\tau^+\tau^-$ decay. The method has been devised to be insensitive to the beamstrahlung which affects the definition of the beam energy at a linear collider. In…

High Energy Physics - Experiment · Physics 2009-11-11 Andre Rouge

Motivated by renewed evidence for new physics in $b \to s\ell\ell$ transitions in the form of LHCb's new measurements of theoretically clean lepton-universality ratios and the purely leptonic $B_s\to\mu^+\mu^-$ decay, we quantify the…

High Energy Physics - Phenomenology · Physics 2021-10-20 Li-Sheng Geng , Benjamín Grinstein , Sebastian Jäger , Shuang-Yi Li , Jorge Martin Camalich , Rui-Xiang Shi

I very briefly review the highlights of the fifth workshop on the physics of the tau lepton and its neutrino. There has been much progress in many sub-fields, which I touch upon in this review: the couplings of the tau to the $Z^0$ and…

High Energy Physics - Experiment · Physics 2009-10-31 Alan J. Weinstein

The measurement of sparticle masses in the Minimal Supersymmetric Standard Model at the LHC is analysed, in the scenario where the lightest neutralino decays into three quarks. Such decays, occurring through the baryon-number violating…

High Energy Physics - Phenomenology · Physics 2011-07-19 B. C. Allanach , A. J. Barr , L. Drage , C. G. Lester , D. Morgan , M. A. Parker , P. Richardson B. R. Webber

We study the lepton-flavor violation processes tau ->mu gamma and mu->e gamma in two different examples of models with non-universal soft breaking terms derived from strings. We show that the predictions are quite different from those of…

High Energy Physics - Phenomenology · Physics 2010-02-03 Daniel F. Carvalho , Mario E. Gomez , Shaaban Khalil

The existence of large \nu_\mu-\nu_\tau mixing suggests the likelihood of large smuon-stau mixing in supersymmetric models, leading to \mu and \tau number violation. In addition to interesting signatures in slepton and neutralino production…

High Energy Physics - Phenomenology · Physics 2009-11-07 Marc Sher