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Related papers: Fine-tuning the low-energy physics

200 papers

The recent evidence for neutrino oscillations stimulate us to discuss again the problem of fermion masses and mixings in gauge theories. In the standard model, several forms for quark mass matrices are equivalent. They become ansatze within…

High Energy Physics - Phenomenology · Physics 2008-11-26 D. Falcone

The up and down quark masses are determined from an optimized QCD Finite Energy Sum Rule (FESR) involving the correlator of axial-vector divergences, to five loop order in Perturbative QCD (PQCD), and including leading non-perturbative QCD…

High Energy Physics - Phenomenology · Physics 2009-01-21 C. A. Dominguez , N. F. Nasrallah , R. H. Röntsch , K. Schilcher

We investigate the fine-tuning problem in the Standard Model and show that Higgs boson and top quark masses consistent with current experimental bounds cannot be obtained unless one extends the particle spectrum. A minimal extension which…

High Energy Physics - Phenomenology · Physics 2009-10-28 Anirban Kundu , Sreerup Raychaudhuri

We calculate the region of the MSSM parameter space (i.e. $M_{1/2}$, $m_{0}$, $\mu$, \ldots) compatible with a correct electroweak breaking and a realistic top-quark mass. To do so we have included {\em all} the one-loop corrections to the…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. de Carlos , J. A. Casas

We determine the top quark mass m_t using t-tbar pairs produced in the D0 detector by \sqrt{s} = 1.8 TeV p-pbar collisions in a 125 pb^-1 exposure at the Fermilab Tevatron. We make a two constraint fit to m_t in t-tbar -> b W^+bbar W^-…

High Energy Physics - Experiment · Physics 2008-11-26 D0 Collaboration , B. Abbott

We present a method to establish experimentally the relation between the top-quark mass $m_t^{MC}$ as implemented in Monte-Carlo generators and the Lagrangian mass parameter $m_t$ in a theoretically well-defined renormalization scheme. We…

High Energy Physics - Phenomenology · Physics 2016-04-27 Jan Kieseler , Katerina Lipka , Sven-Olaf Moch

Decoupling of heavy quarks at low energies can be described by means of an effective theory as shown by S. Weinberg in Ref. [1]. We study the decoupling of the charm quark by lattice simulations. We simulate a model, QCD with two degenerate…

High Energy Physics - Lattice · Physics 2017-11-22 Francesco Knechtli , Tomasz Korzec , Björn Leder , Graham Moir

We present a complete study of the vacuum structure of Top Quark Seesaw models of the Electroweak Symmetry Breaking, including bottom quark mass generation. Such models emerge naturally from extra dimensions. We perform a systematic gap…

High Energy Physics - Phenomenology · Physics 2008-11-26 Hong-Jian He , Christopher T. Hill , T. Tait

We study large top quark mass effects on low energy physics in the chiral Lagrangian formulated electroweak theories. We show that these radiative corrections can be easily obtained from a set of Feynman diagrams involving only the scalar…

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

Weak scale supersymmetry has a generic problem of fine-tuning in reproducing the correct scale for electroweak symmetry breaking. The problem is particularly severe in the minimal supersymmetric extension of the standard model (MSSM). We…

High Energy Physics - Phenomenology · Physics 2009-09-29 Ryuichiro Kitano , Yasunori Nomura

We study dynamical symmetry breaking in the Standard Model including the next-to-leading order terms. We introduce at a high, but finite, energy scale Lambda a top quark condensate H={t {bar t}} and derive, using path integral methods, the…

High Energy Physics - Phenomenology · Physics 2009-10-28 G. Cvetic , E. A. Paschos , N. D. Vlachos

We stress the importance of the circa 20 parameters in the Standard Model, which are not fixed by the model but only determined experimentally, as a window to the physics beyond the Standard Model. However, it is a tiny window in as far as…

High Energy Physics - Phenomenology · Physics 2015-06-25 C. D. Froggatt , H. B. Nielsen

We calculate the top quark loop corrections to the Zbb vertex in the chiral lagrangian of the dynamical electroweak symmetry breaking theory. We use the effective lagrangian based on coset space SU(2) X U(1) / U(1) with the gauge…

High Energy Physics - Phenomenology · Physics 2009-10-28 X. Zhang

In a recent article, we proposed an energy correlator-based method to achieve a precision top quark mass extraction from jet substructure, using the $W$-boson mass as a standard candle. In this paper, we perform an extensive event generator…

High Energy Physics - Phenomenology · Physics 2024-12-19 Jack Holguin , Ian Moult , Aditya Pathak , Massimiliano Procura , Robert Schöfbeck , Dennis Schwarz

We generalize and update our former top quark mass calibration framework for Monte Carlo (MC) event generators based on the $e^+e^-$ hadron-level 2-jettiness $\tau_2$ distribution in the resonance region for boosted $t\bar t$ production,…

High Energy Physics - Phenomenology · Physics 2023-12-12 Bahman Dehnadi , André H. Hoang , Oliver L. Jin , Vicent Mateu

If the quadratic divergence of the standard electroweak model and its local variation with mass scale are both assumed to be zero, then a modified one-loop calculation yields m_t = 117 GeV and m_H = 183 GeV. Such a scenario may be the…

High Energy Physics - Phenomenology · Physics 2015-06-25 Ernest Ma

Reaching a high precision of the top quark mass is an important task of the Large Hadron Collider. We perform a feasibility study of measuring the top quark mass through the three-point energy correlator. The expected sensitivity of the top…

High Energy Physics - Phenomenology · Physics 2024-10-14 Meng Xiao , Yulei Ye , Xinyu Zhu

The quadratic divergences in the scalar sector of the standard model are considered. Since the divergences are present also in the unbroken theory, a natural scale for the divergence formula is proposed to be at the scale of new physics.…

High Energy Physics - Phenomenology · Physics 2009-10-28 Masud Chaichian , Ricardo Gonzalez Felipe , Katri Huitu

A simultaneous measurement of the top-quark, W-boson, and neutrino masses is reported for t t-bar events selected in the dilepton final state from a data sample corresponding to an integrated luminosity of 5.0 inverse femtobarns collected…

High Energy Physics - Experiment · Physics 2013-07-30 CMS Collaboration

If supersymmetry is broken directly to the Standard Model at energies not very far from the unified scale, the Higgs boson mass lies in the range 128-141 GeV. The end points of this range are tightly determined. Theories with the Higgs…

High Energy Physics - Phenomenology · Physics 2015-05-14 Lawrence J. Hall , Yasunori Nomura