相关论文: Precision Electroweak Measurements Circa 2002
The observed Higgs boson mass and the naturalness argument leave us a narrow window for the soft mass spectrum in natural supersymmetry that can be studied through the electroweak precision tests (EWPTs). We divide the analysis into the…
I present a model addressing coherently the naturalness problem of the electroweak scale and the observed pattern of deviations from the Standard Model in semi-leptonic decays of $B$ mesons. The Higgs and the two scalar leptoquarks…
Until recently precision electroweak computations were fundamentally uncertain due to lack of knowledge about the existence of the Standard Model Higgs boson and its mass. For this reason substantial calculational machinery had to be…
With the discovery of the Higgs boson, the spectrum of particles in the Standard Model (SM) is complete. It is more important than ever to perform precision measurements and to test for deviations from SM predictions in the electroweak…
Higgs decays to gauge boson pairs are a crucial ingredient in the study of Higgs properties, with the decay $H\rightarrow\gamma\gamma$ being particularly sensitive to new physics effects. Assuming all potential new physics occurs at…
1. Introduction 2. Status of the Data 3. Precision Electroweak Data and the Standard Model 4. A More General Analysis of Electroweak Data 4.1 Basic Definitions and Results 4.2 Experimental Determination of the Epsilon Variables 4.3…
We study vertex corrections to the leptonic electroweak observables in the general MSSM at tan(beta) < 35. In particular, we address the question of whether supersymmetry can be responsible for the observed 2 sigma deviation from the…
This paper is an updated version of the lectures given at the XXIX International Meeting on Fundamental Physics in Sitges, Barcelona (February 2000). The measurements perforned at LEP and SLC have substantially improved the precision of the…
The most precise measurement of the weak mixing angle sin^2(theta) at LEP is from the forward-backward asymmetry e+e- --> bbbar at the Z-pole. In this note the QED and electroweak radiative corrections to obtain the pole asymmetry from the…
The precision measurements of lepton electroweak parameters at SLD and LEP are reviewed and discussed. The updated SLD weak mixing angle measurement from $A_{LR}$ and the lepton left-right forward-backward asymmetries is…
The CDF collaboration recently reported a new precise measurement of the $W$ boson mass $M_W$ with a central value significantly larger than the SM prediction. We explore the effects of including this new measurement on a fit of the…
We consider the Type-II seesaw model extended with another Higgs doublet, which is odd under the $Z_2$ symmetry. We look for the possibility of triggering the electroweak symmetry breaking via radiative effects. The Higgs mass parameter…
The impact of atomic parity violation experiments on determination of the weak mixing parameter $\sin^2 \theta$ and the Peskin-Takeuchi parameters $S$ and $T$ is reassessed in the light of recent electroweak measurements at LEP, SLAC, and…
A global analysis is performed using the latest data from LEP and SLC. Constraints on the electroweak universal parameters ($S,T,U$) and on the masses of the top quark and Higgs boson within the Standard Model (SM) are investigated. The…
The fit of precision electroweak data to the Minimal Standard Model currently gives an upper limit on the Higgs boson mass of 170 GeV at 95% confidence. Nevertheless, it is often said that the Higgs boson could be much heavier in more…
I summarize recent developments in electroweak precision physics and global fits. Expectations for future measurements, both at lower energies and the energy frontier, are also discussed.
The electroweak symmetry may be broken by a composite Higgs which arises naturally as a bound state of the top quark if the standard model gauge fields and fermions propagate in extra dimenions. The top quark mass and the Higgs mass can be…
We argue that the present value and accuracy of $M_W$ and $m_t$ measurements tend to favor the MSSM over the SM. By speculating that a precision of the order 40 MeV and 3 GeV respectively for $M_W$ and $m_t$ will be achieved at LEP2 and…
The main purpose of this thesis is to discuss the impact of electroweak precision measurements on the present knowledge of particle physics, both in the framework of the Standard Model and of its most straightforward extensions. In Chapter…
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…