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Related papers: Z-pole observables in an effective theory

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The new measurement of the $W$-boson mass from the CDF collaboration shows a significant tension with the Standard Model prediction. We quantify this discrepancy within a state-of-the-art analysis of electroweak precision data and…

High Energy Physics - Phenomenology · Physics 2022-08-17 Ayan Paul , Mauro Valli

If neutrinos are Dirac particles and, as suggested by the so far null LHC results, any new physics lies at energies well above the electroweak scale, the Standard Model effective field theory has to be extended with operators involving the…

High Energy Physics - Phenomenology · Physics 2019-08-26 Julien Alcaide , Shankha Banerjee , Mikael Chala , Arsenii Titov

We present results from a global fit of Standard Model parameters and dimension-6 SMEFT Wilson coefficients that includes electroweak, Drell-Yan, Higgs-boson, top-quark, and flavour observables. Fits obtained by floating individual…

High Energy Physics - Phenomenology · Physics 2026-03-16 J. de Blas , A. Goncalves , V. Miralles , L. Reina , L. Silvestrini , M. Valli

We study the sensitivity to physics beyond the standard model of precise top-quark pair production measurements at future lepton colliders. A global effective-field-theory approach is employed, including all dimension-six operators of the…

High Energy Physics - Phenomenology · Physics 2018-11-14 Gauthier Durieux , Martín Perelló , Marcel Vos , Cen Zhang

The Standard Model (SM) with a light Higgs boson provides a very good description of the precision electroweak observable data coming from the LEP, SLD and Tevatron experiments. Most of the observables, with the notable exception of the…

High Energy Physics - Phenomenology · Physics 2010-04-06 D. Choudhury , T. M. P. Tait , C. E. M. Wagner

The CDF and D0 experiments have reported on the measurement of the forward-backward asymmetry of top quark pair production at the Tevatron and the result is that it is more than 2 standard deviations above the predicted value in the…

High Energy Physics - Phenomenology · Physics 2011-05-24 Abdelhak Djouadi , Gregory Moreau , Francois Richard , Ritesh K. Singh

We explore the constraints which can be derived on Wilson coefficients in the Standard Model Effective Field Theory from dilepton production, notably including the constraints on operators which do not lead to cross sections growing with…

High Energy Physics - Phenomenology · Physics 2021-03-31 Alyssa Horne , Jordan Pittman , Marcus Snedeker , William Shepherd , Joel W. Walker

The quest for new sources of the simultaneous violation of $C$ and $CP$ symmetry was popular in the 1960s and has since been mostly neglected for more than half a century. In this work we revisit fundamental quark-level operators that break…

High Energy Physics - Phenomenology · Physics 2023-06-30 Hakan Akdag , Bastian Kubis , Andreas Wirzba

Effective theories are well established theoretical frameworks to describe the effect of energetically widely separated UV models on observables at lower energy scales. Due to the complexity of the effective theory when taking all the…

High Energy Physics - Phenomenology · Physics 2021-03-31 Supratim Das Bakshi , Joydeep Chakrabortty , Michael Spannowsky

We consider the two Higgs doublet model extension of the Standard Model in the limit where all physical scalar particles are very heavy; too heavy, in fact, to be experimentally produced in forthcoming experiments. The symmetry breaking…

High Energy Physics - Phenomenology · Physics 2009-10-30 P. Ciafaloni , D. Espriu

We present a global analysis of the B->K*(->K pi)mu+mu- decay using the recent LHCb measurements of the primary observables P_{1,2} and P'_{4,5,6,8}. Some of them exhibit large deviations with respect to the SM predictions. We explain the…

High Energy Physics - Phenomenology · Physics 2015-06-16 Sebastien Descotes-Genon , Joaquim Matias , Javier Virto

Inspired by recent lattice measurements, we determine the short-distance (a << r << 1/pi T) as well as large-frequency (1/a >> omega >> pi T) asymptotics of scalar (trace anomaly) and pseudoscalar (topological charge density) correlators at…

High Energy Physics - Phenomenology · Physics 2010-12-09 M. Laine , M. Vepsalainen , A. Vuorinen

We derive model-independent constraints arising from the Z and W boson observables on dimension six operators in the effective theory beyond the Standard Model. In particular, we discuss the generic flavor structure for these operators as…

High Energy Physics - Phenomenology · Physics 2015-08-04 Aielet Efrati , Adam Falkowski , Yotam Soreq

The top quark forward-backward asymmetry measured at the Tevatron collider shows a large deviation from standard model expectations. Among possible interpretations, a non-universal $Z^\prime$ model is of particular interest as it naturally…

High Energy Physics - Phenomenology · Physics 2011-05-23 Edmond L. Berger , Qing-Hong Cao , Chuan-Ren Chen , Chong Sheng Li , Hao Zhang

We know there is new physics at the electroweak scale, but we don't know what it is. Right now, the top quark is our only window on to this physics. In almost all models of electroweak symmetry breaking, top either couples strongly to new…

High Energy Physics - Experiment · Physics 2007-05-23 John Womersley

This paper complements the study of single top production at the LHC aiming to estimate the sensitivity of different observables to the magnitude of the effective couplings. In a previous paper the dominant $W$-gluon fusion mechanism was…

High Energy Physics - Phenomenology · Physics 2008-11-26 D. Espriu , J. Manzano

We discuss how the leading electroweak Higgs production processes at the LHC, namely vector-boson fusion and Higgs+W/Z associated production, can be characterized in generic extensions of the Standard Model by a proper set of…

High Energy Physics - Phenomenology · Physics 2016-04-20 Admir Greljo , Gino Isidori , Jonas M. Lindert , David Marzocca

The measured value of A_b, the Z \bar bb asymmetry parameter, disagrees with the Standard Model at 99% confidence level. If genuine the discrepancy could indicate new interactions unique to third generation quarks, implying enhanced Z…

High Energy Physics - Phenomenology · Physics 2007-05-23 Michael S. Chanowitz

We reassess non-standard triple gauge couplings in the light of the recent $(g-2)_\mu$ measurement at FNAL, the new lattice theory result of $(g-2)_\mu$ and the updated measurements of several $B$-decay modes. In the framework of SMEFT,…

High Energy Physics - Phenomenology · Physics 2023-01-04 Debajyoti Choudhury , Kuldeep Deka , Suvam Maharana , Lalit Kumar Saini

Employing the framework of the Standard Model Effective Field Theory, we perform a detailed reinterpretation of measurements of the Weinberg angle in dilepton production as a search for new-physics effects. We truncate our signal prediction…

High Energy Physics - Phenomenology · Physics 2019-09-04 Stefan Alte , Matthias König , William Shepherd
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