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Related papers: Rb and Heavy Quark Mixing

200 papers

Recent heavy flavour results from the LEP experiments are presented. These include a search for new physics in rare B decays, a new model-independent measurement of the b-quark fragmentation function at the Z peak, updated measurements of…

High Energy Physics - Experiment · Physics 2007-05-23 O. Schneider

A scenario is presented where the $s$, $c$, and $b$ quark fusion Higgs production cross sections are enhanced with respect to those of the Standard Model. In particular the $c$ quark fusion production is very important and can account for a…

High Energy Physics - Phenomenology · Physics 2011-07-04 Alfredo Aranda , J. Lorenzo Diaz-Cruz , Alfonso Rosado

Recent developments in models with warped extra dimensions have opened new possibilities for vector-like quark studies at hadron colliders. These new vector-like quarks can mix sizably with light Standard Model quarks without violating low…

High Energy Physics - Phenomenology · Physics 2009-11-13 Anupama Atre , Marcela Carena , Tao Han , Jose Santiago

This paper emphasizes four topics that represent some of the year's highlights in heavy quark physics. First of all, a review is given of charm lifetime measurements and how they lead to better understanding of the mechanisms of charm…

High Energy Physics - Experiment · Physics 2010-11-23 Guy Blaylock

Highlights of measurements of the properties of the top quark at the LHC are presented. The measurements probe a range of the properties of the top quark, including the structure of the $Wtb$ vertex, the top-Z coupling and the top-quark…

High Energy Physics - Experiment · Physics 2017-05-26 Mark Owen

New physics effects on the $B^0-\bar{B}^0$ mixing and B-decay amplitudes are discussed. By a combined analysis, the model of new physics can be partially distinguished.It is emphasized that the extraction of unitarity angles $\beta$ and…

High Energy Physics - Phenomenology · Physics 2014-11-17 Y. F. Zhou , Y. L. Wu

The most general parametrization of the $tbW$ vertex includes a right coupling $V_R$ that is zero at tree level in the standard model. This quantity may be measured at the Large Hadron Collider where the physics of the top decay is…

High Energy Physics - Phenomenology · Physics 2016-01-27 Gabriel A. González-Sprinberg , Jordi Vidal

We explore models with additional right-handed gauge bosons that couple predominantly to the third generation in the context of $b\bar{b}$ production at LEP. In particular we investigate potential new contributions to $\delta g_{Rb}$ that…

High Energy Physics - Phenomenology · Physics 2009-11-10 X. -G. He , G. Valencia

The 1999 precision electroweak data from LEP and SLC persist in showing some slight discrepancies from the assumed standard model, mostly regarding $b$ and $c$ quarks. We show how their mixing with exotic heavy quarks could result in a more…

High Energy Physics - Phenomenology · Physics 2009-10-31 Darwin Chang , We-Fu Chang , Ernest Ma

There have been several important recent developments in precision electroweak tests. These include: the new LEP energy scan during the 1993 run; the first high-precision results on the left-right asymmetry from the SLD Collaboration at…

High Energy Physics - Phenomenology · Physics 2007-05-23 Paul Langacker

The relativistic quark model is presented. The quark-antiquark potential for the Schroedinger-like equation is constructed with the account of retardation effects and one-loop radiative corrections. It consists of the one-gluon exchange…

High Energy Physics - Phenomenology · Physics 2009-11-07 D. Ebert , R. N. Faustov , V. O. Galkin

Some of the recent progress in heavy quark physics is reviewed. Special attention is paid to inclusive methods for determining Vub and factorization in nonleptonic B decays. Theoretical predictions for top-antitop production near threshold…

High Energy Physics - Phenomenology · Physics 2009-11-07 Mark B. Wise

We conduct a systematic study of the impact of new physics in quark-level $b \to c \bar{c} s$ transitions on $B$-physics, in particular rare $B$-decays and $B$-meson lifetime observables. We find viable scenarios where a sizable effect in…

High Energy Physics - Phenomenology · Physics 2018-08-07 Sebastian Jäger , Matthew Kirk , Alexander Lenz , Kirsten Leslie

We review the highlights of quark mixing, particle-antiparticle mixing, CP violation and rare K- and B-decays in the Standard Model. The top quark discovery, the precise measurement of its mass, the improved knowledge of the couplings…

High Energy Physics - Phenomenology · Physics 2016-11-03 Andrzej J. Buras , Robert Fleischer

We estimate, in a large class of scenarios, the sensitivity to new physics in B_d and B_s mixings achievable with 50 ab-1 of Belle II and 50 fb-1 of LHCb data. We find that current limits on new physics contributions in both B_{d,s} systems…

High Energy Physics - Phenomenology · Physics 2014-03-05 Jerome Charles , Sebastien Descotes-Genon , Zoltan Ligeti , Stephane Monteil , Michele Papucci , Karim Trabelsi

We propose a new relation between quark mixing matrix and lepton mixing matrix. Since the parameters in the quark sector are well determined, we employ them to describe the mixing of leptons. Phenomenologically, we study the neutrino…

High Energy Physics - Phenomenology · Physics 2011-08-02 Nan Qin , Bo-Qiang Ma

Constraints on the two Higgs doublet model are presented, assuming a top mass of 174 $\pm$ 17 GeV. We concentrate primarily on the ``type II'' model, where up--type quarks receive their mass from one Higgs doublet, and down--type quarks…

High Energy Physics - Phenomenology · Physics 2010-11-01 Aaron K. Grant

The polarizations of the heavy quark ($q=t$ or $b$) in the process $e^+e^- \to q \bar q h$ have been calculated in the general two Higgs doublet model. The CP violating normal polarization of the top quark can reach 8%, and $2 \sim 3%$ for…

High Energy Physics - Phenomenology · Physics 2009-11-07 Chao-Shang Huang , Shou-hua Zhu

The top flavour-changing neutral couplings can be large in extended models with vector-like quarks. In the next decade(s) the CERN Large Hadron Collider will allow to measure (bound) them with a precision of few per cent.

High Energy Physics - Phenomenology · Physics 2011-03-02 F. del Aguila

We present a detailed analysis of the use of heavy quark fragmentation into heavy hadrons for testing the heavy quark effective theory through comparison of the measured fragmentation parameters of the $c$ and $b$ quarks. Our analysis is…

High Energy Physics - Phenomenology · Physics 2009-09-25 L. Randall , N. Rius