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Related papers: Lorentz Violation in Top-Quark Physics

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An overview of recent progress on testing Lorentz and CPT symmetry using Penning traps is presented. The theory of quantum electrodynamics with Lorentz-violating operators of mass dimensions up to six is summarized. Dominant shifts in the…

High Energy Physics - Phenomenology · Physics 2021-09-17 Yunhua Ding , Teague D. Olewiler , Mohammad Farhan Rawnak

In a model with Lorentz invariance violation implemented through modified dispersion relations, we estimate the rate for the decay process gamma -> 3 gamma and find that it provides a relevant bound on Lorentz invariance violation.

High Energy Physics - Phenomenology · Physics 2009-11-11 Graciela Gelmini , Shmuel Nussinov , Carlos E. Yaguna

In this conference proceedings, some comments on the present status and recent growth of efforts to find Lorentz and CPT violation are given by extracting metrics from the annually updated "Data Tables for Lorentz and CPT Violation." They…

High Energy Physics - Phenomenology · Physics 2019-12-23 Neil Russell

Observations of the synchrotron and inverse Compton emissions from ultrarelativistic electrons in astrophysical sources can reveal a great deal about the energy-momentum relations of those electrons. They can thus be used to place bounds on…

High Energy Physics - Phenomenology · Physics 2021-04-19 Brett Altschul

We propose a simple phenomenological model predicting, through Lorentz symmetry breaking, a CPT-violating asymmetry between particle and antiparticle states in neutrino oscillations involving sterile neutrinos. Such a model is able to…

High Energy Physics - Phenomenology · Physics 2014-11-20 S. Esposito , G. Salesi

Below the electroweak scale, new physics that violates lepton number in two units ($\Delta L = 2$) and is mediated by heavy particle exchange can be parameterized by a dimension-9 low-energy effective Lagrangian. Operators in this…

High Energy Physics - Phenomenology · Physics 2025-03-11 Marcela González , Nicolás A. Neill

A direct search for charged lepton-flavour violation in top-quark decays is presented. The data analysed correspond to $79.8\ \text{fb}^{-1}$ of proton--proton collisions at a centre-of-mass energy of $\sqrt{s}=13\ \text{TeV}$ recorded by…

High Energy Physics - Experiment · Physics 2018-09-25 Carlo A. Gottardo

We study the potential of future lepton colliders to probe violation of the CP symmetry in the top quark sector. In certain extensions of the Standard Model, such as the two-Higgs-doublet model (2HDM), sizeable anomalous top quark dipole…

High Energy Physics - Experiment · Physics 2018-04-04 W. Bernreuther , L. Chen , I. García , M. Perelló , R. Poeschl F. Richard , E. Ros , M. Vos

The behavior of photons in the presence of Lorentz and CPT violation is studied. Allowing for operators of arbitrary mass dimension, we classify all gauge-invariant Lorentz- and CPT-violating terms in the quadratic Lagrange density…

High Energy Physics - Phenomenology · Physics 2009-09-02 Alan Kostelecky , Matthew Mewes

A search is performed for charged-lepton flavor violating processes in top quark (t) production and decay. The data were collected by the CMS experiment from proton-proton collisions at a center-of-mass energy of 13 TeV and correspond to an…

High Energy Physics - Experiment · Physics 2025-01-31 CMS Collaboration

In this talk, I discuss possible bounds on the Lorentz and CPT violating parameters in the Higgs sector of the so called minimal standard model extension. The main motivation to this study is coming from the fact that unlike the parameters…

High Energy Physics - Phenomenology · Physics 2009-11-10 Ismail Turan

We consider an extended QED with the addition of a dimension-five Lorentz-breaking coupling between spinor and gauge fields, involving a pseudo-tensor $\kappa^{\mu\nu\lambda\rho}$. The specific form of the Lorentz violating coupling…

High Energy Physics - Theory · Physics 2023-02-02 A. J. G. Carvalho , A. F. Ferrari , A. M. de Lima , J. R. Nascimento , A. Yu. Petrov

Top-quark pair production is central to many facets of LHC physics. At leading order, the top and anti-top are produced in a back-to-back topology, however this topology accounts only for a minority of $t \bar t$ events with TeV-scale…

High Energy Physics - Phenomenology · Physics 2021-07-28 Fabrizio Caola , Frédéric A. Dreyer , Ross W. McDonald , Gavin P. Salam

We study the T odd correlations induced by CP violating anomalous top-quark couplings at both production and decay level in the process gg --> t t_bar --> (b mu+ nu_mu) (b_bar mu- nu_mu_bar). We consider several counting asymmetries at the…

High Energy Physics - Phenomenology · Physics 2014-11-18 Sudhir Kumar Gupta , Alaettin Serhan Mete , G. Valencia

Various studies have already considered radiative corrections in Lorentz-violating models unveiling many instances where a minimal or nonminimal operator generates, via loop corrections, a contribution to the photon sector of the…

High Energy Physics - Phenomenology · Physics 2019-07-03 A. F. Ferrari

We explore $\mathcal CP$-violation effects of Higgs-top interactions in the associated production of a Higgs boson with top-pair in the dileptonic decay modes of top-quark originating from proton proton collisions $pp \to t\bar{t}H \to (l^+…

High Energy Physics - Phenomenology · Physics 2023-08-08 Apurba Tiwari , Sudhir Kumar Gupta

This talk summarizes some recent experimental constraints on Lorentz and CPT violation.

High Energy Physics - Phenomenology · Physics 2007-05-23 Alan Kostelecky

To date, a significant effort has been made to adddress the Lorentz violating standard model in low-energy systems, but little is known about the ramifications for high-energy cross sections. In this talk, I discuss the modified Feynman…

High Energy Physics - Phenomenology · Physics 2017-08-23 Don Colladay

We study the Lorentz and CPT violating effects on the ratio \frac{BR_{LorVio}}{BR_{SM}}, where BR_{LorVio} (BR_{SM}) is the branching ratios coming from the Lorentz violating effects (the SM), for the decays H^0\to f^+ f^- (f= quarks and…

High Energy Physics - Phenomenology · Physics 2009-11-10 E. O. Iltan

The O(alpha m_t^2/m_W^2) corrections to top quark pair production by gluon-gluon fusion at the LHC are calculated in two-Higgs-doublet models. We find that the correction to the cross-section can exceed about -10% for certain parameter…

High Energy Physics - Phenomenology · Physics 2009-10-28 Hong-Yi Zhou , Chong-Sheng Li , Yu-Ping Kuang