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Related papers: Testing Extended Technicolor With $R_b$

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We study the effect of bulk fermions on electroweak precision observables in a recently proposed model with warped extra dimensions and no custodial symmetry. We find that the top-quark mass, together with the corrections to the Zbb vertex…

High Energy Physics - Phenomenology · Physics 2015-05-28 Adrian Carmona , Eduardo Ponton , Jose Santiago

Assuming that the actual values of $m_t$ and the data set ($\Gamma_b$, $\Gamma_h$, $\Gamma_Z$, $R_b$, $R_c$, $R_l$) are within their $1-\sigma$ errors as reported by CDF, D0 and by LEP Collaborations, the parameter $\Delta^{new}_b$ which…

High Energy Physics - Phenomenology · Physics 2007-05-23 Zhenjun Xiao , Shunmin Liu , Xuelei Wang , Lingde Wan , Gongru Lu

We use the framework of dark matter effective field theories to study the complementarity of bounds for a dark matter particle with mass in the MeV range. Taking properly into account the mixing between operators induced by the…

High Energy Physics - Phenomenology · Physics 2017-10-25 Enrico Bertuzzo , Cristian J. Caniu Barros , Giovanni Grilli di Cortona

If there is new physics associated with the top quark, it could show up as anomalous couplings of the top quark to weak gauge bosons, such as $Z\ttbar$ and $W\tbbar$ vector and axial-vector couplings. We use the processes $\ttbar\to…

High Energy Physics - Phenomenology · Physics 2009-10-28 M. Hosch , K. Whisnant , Bing-Lin Young

In several unified field theories the torsion trace is set equal to the electromagnetic potential. Using fibre bundle techniques we show that this is no leading principle but a formal consequence of another geometric relation between…

High Energy Physics - Theory · Physics 2008-02-03 Kenichi Horie

The Strongly Coupled Standard Model predicts a rich spectrum of excited states at the Fermi scale. We study the first radial excitations of the vector bosons. The inclusion of these new states affects the low energy phenomenology of the…

High Energy Physics - Phenomenology · Physics 2009-07-30 Francesco D'Eramo

We explore the radiative corrections to the process $Z \to b \bar b$ in models with extended Higgs sectors. The observables $R_b = \Gamma(Z \to b \bar b)/\Gamma(Z \to \rm{hadrons})$ and the $Z b \bar b$ coupling asymmetry, $A_b = (g_L^2 -…

High Energy Physics - Phenomenology · Physics 2009-10-31 Howard E. Haber , Heather E. Logan

We propose a new strategy to probe the $Z$ boson couplings to bottom and charm quarks at the LHC. In this work we mainly focus on the case of bottom quarks. Here, the $Z$ boson is produced in association with two $b$-jets and decays to…

High Energy Physics - Phenomenology · Physics 2023-06-28 Fady Bishara , Zhuoni Qian

In Networked Control Systems (NCS), the absence of physical communication links in the loop leads to relevant issues, such as measurement delays and asynchronous execution of the control commands. These issues may lead to unwanted control…

Systems and Control · Electrical Eng. & Systems 2022-11-16 Luca Nanu , Carlos Perez Montenegro , Luigi Colangelo , Carlo Novara

In this work, we establish risk bounds for the Empirical Risk Minimization (ERM) with both dependent and heavy-tailed data-generating processes. We do so by extending the seminal works of Mendelson [Men15, Men18] on the analysis of ERM with…

Statistics Theory · Mathematics 2021-09-14 Abhishek Roy , Krishnakumar Balasubramanian , Murat A. Erdogdu

We analyze the diagonal and transition magnetic and electric dipole moments of charged leptons in extended technicolor (ETC) models, taking account of the multiscale nature of the ETC gauge symmetry breaking, conformal (walking) behavior of…

High Energy Physics - Phenomenology · Physics 2009-11-10 Thomas Appelquist , Maurizio Piai , Robert Shrock

We study diagonal and transition quark dipole operators in a class of extended technicolor (ETC) models, taking account of the multiscale nature of the ETC gauge symmetry breaking and of the mixing among ETC interaction eigenstates. Because…

High Energy Physics - Phenomenology · Physics 2009-11-10 Thomas Appelquist , Maurizio Piai , Robert Shrock

Motivated by $-2 \sigma$ deviation from the Standard Model prediction for the forward--backward asymmetry of $Z \to b \bar{b}$ decay in the LEP data, we explore the anomalous couplings of $Z b \bar{b}$ vertex through the electroweak…

High Energy Physics - Phenomenology · Physics 2009-10-31 Kang Young Lee

Generative models offer a direct way of modeling complex data. Energy-based models attempt to encode the statistical correlations observed in the data at the level of the Boltzmann weight associated with an energy function in the form of a…

Disordered Systems and Neural Networks · Physics 2024-04-10 Aurélien Decelle , Cyril Furtlehner , Alfonso De Jesus Navas Gómez , Beatriz Seoane

We review the status of heavy neutral gauge bosons, Z', with emphasis on constraints that arise in supersymmetric models, especially those motivated from superstring compactifications. We first summarize the current phenomenological…

High Energy Physics - Phenomenology · Physics 2016-11-03 M. Cvetic , P. Langacker

We discuss a few tests of the ER=EPR proposal. We consider certain conceptual issues as well as explicit physical examples that could be experimentally realized. In particular, we discuss the role of the Bell bounds, the large N limit, as…

High Energy Physics - Theory · Physics 2020-09-23 De-Chang Dai , Djordje Minic , Dejan Stojkovic , Changbo Fu

The strongest constraint on Vtb presently comes from the 3 x 3 unitarity of the CKM matrix, which fixes Vtb to be very close to one. If the unitarity is relaxed, current information from top production at Tevatron still leaves open the…

High Energy Physics - Phenomenology · Physics 2014-11-18 J. Alwall , R. Frederix , J. -M. Gerard , A. Giammanco , M. Herquet , S. Kalinin , E. Kou , V. Lemaitre , F. Maltoni

The sensitivity of experiments with neutral mesons to possible indirect CPT violation is examined. It is shown that experiments conventionally regarded as equivalent can have CPT reaches differing by orders of magnitude within the framework…

High Energy Physics - Phenomenology · Physics 2009-09-25 Alan Kostelecky

We parameterize the non-universal couplings of t-t-Z and t-b-W in the electroweak chiral lagrangian approach, and examine the constraints on these parameters from the LEP data. We also study how the SLC, Tevatron, LHC and NLC can improve…

High Energy Physics - Phenomenology · Physics 2009-10-28 Douglas O. Carlson , Ehab Malkawi , C. --P. Yuan

We relate all $C$-- and $P$--invariant anomalous triple vector--boson couplings to the oblique electroweak parameters. LEP constraints on the latter then yield the strongest and most general simultaneous bounds to date on the former. Even…

High Energy Physics - Phenomenology · Physics 2008-02-03 Debajyoti Choudhury , Probir Roy , Rahul Sinha