scholarly journals ELECTROWEAK MEASUREMENTS

2006 ◽  
Vol 21 (08n09) ◽  
pp. 1604-1616 ◽  
Author(s):  
CRISTINEL DIACONU
Keyword(s):  
Standard Model ◽  
W Boson ◽  
Low Energy ◽  
Precision Measurements ◽  
Production Processes ◽  
The Standard Model ◽  
The Status ◽  
Electroweak Sector

The measurements of electroweak sector of the Standard Model are presented, including most recent results from LEP, Tevatron and HERA colliders. The robustness of the Standard Model is illustrated with the precision measurements, the electroweak fits and the comparisons to the results obtained from low energy experiments. The status of the measurements of the W boson properties and rare production processes involving weak bosons at colliders is examined, together with the measurements of the electroweak parameters in ep collisions.

scholarly journals PRECISION SUPERSYMMETRY MEASUREMENTS AT THE e-e- COLLIDER

1998 ◽  
Vol 13 (14) ◽  
pp. 2329-2336 ◽  
Author(s):  
HSIN-CHIA CHENG
Keyword(s):  
Standard Model ◽  
High Precision ◽  
Gauge Boson ◽  
Linear Collider ◽  
Direct Detection ◽  
Precision Measurements ◽  
Supersymmetric Particle ◽  
The Standard Model ◽  
Electroweak Sector ◽  
Future Linear Collider

Measurements of supersymmetric particle couplings provide important verification of supersymmetry. If some of the superpartners are at the multi-TeV scale, they will escape direct detection at planned future colliders. However, such particles induce nondecoupling corrections in processes involving the accessible superparticles through violations of the supersymmetric equivalence between gauge boson and gaugino couplings. These violations are analogous to the oblique corrections in the electroweak sector of the Standard Model, and can be parametrized in terms of super-oblique parameters. The e-e- collision mode of a future linear collider is shown to be an excellent environment for such high precision measurements of these SUSY parameters, which will provide an important probe of superparticles beyond reachable energies.

scholarly journals RECENT DEVELOPMENTS IN PHYSICS BEYOND THE STANDARD MODEL

2000 ◽  
Vol 15 (supp01a) ◽  
pp. 440-463 ◽  
Author(s):  
GIAN F. GIUDICE
Keyword(s):  
Standard Model ◽  
Recent Work ◽  
Low Energy ◽  
Neutrino Masses ◽  
Beyond The Standard Model ◽  
The Standard Model ◽  
Spatial Dimensions ◽  
The Status ◽  
Recent Developments

In this talk I discuss what I believe are the most interesting recent developments in physics beyond the Standard Model. After some initial comments on neutrino masses, I discuss the status of low-energy supersymmetry and finally turn to describing some recent work in theories with extra spatial dimensions.

scholarly journals Precision Measurements of the W Boson Mass

2000 ◽  
Vol 50 (1) ◽  
pp. 207-248 ◽  
Author(s):  
Douglas A. Glenzinski ◽  
Ulrich Heintz
Keyword(s):  
Standard Model ◽  
W Boson ◽  
New Physics ◽  
Boson Mass ◽  
Precision Measurements ◽  
Experimental Measurements ◽  
Great Success ◽  
Fundamental Parameter ◽  
The Past ◽  
The Standard Model

▪ Abstract  The standard model of electroweak interactions has had great success in describing the observed data over the past three decades. The precision of experimental measurements affords tests of the standard model at the quantum loop level beyond leading order. Despite this success, it is important to continue confronting experimental measurements with the standard model's predictions because any deviation would signal new physics. As a fundamental parameter of the standard model, the mass of the W boson, MW, is of particular importance. Aside from being an important test of the model itself, a precision measurement of MW can be used to constrain the mass of the Higgs boson, MH. In this article, we review the principal experimental techniques for determining MW and discuss their combination into a single precision MW measurement. We conclude by briefly discussing future prospects for precision measurements of the W boson mass.

scholarly journals NEW PHYSICS EFFECTS IN THE FLAVOR-CHANGING NEUTRAL COUPLINGS OF THE TOP QUARK

2006 ◽  
Vol 21 (17) ◽  
pp. 3473-3493 ◽  
Author(s):  
F. LARIOS ◽  
R. MARTÍNEZ ◽  
M. A. PÉREZ
Keyword(s):  
Standard Model ◽  
Top Quark ◽  
New Physics ◽  
Low Energy ◽  
Precision Measurements ◽  
Flavor Changing ◽  
The Standard Model

We survey the flavor-changing neutral couplings (FCNC) of the top quark predicted by some extensions of the Standard Model: THDM, SUSY, Left–Right symmetric, TC2, 331, and models with extra quarks. Since the expected sensitivity of the LHC and ILC for the tcV (V = γ, g, Z) and tcH couplings is of order of a few percent, we emphasize the importance of any new physics effect that gives a prediction for these FCNC couplings within this limit. We also review the constraints imposed on these couplings from low-energy precision measurements.

scholarly journals Flavour Anomalies in a U(1) SUSY Extension of the SM

Symmetry ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 191
Author(s):  
Alexander Bednyakov ◽  
Alfiia Mukhaeva
Keyword(s):  
Standard Model ◽  
Parameter Space ◽  
Gauge Boson ◽  
New Physics ◽  
Low Energy ◽  
Effective Theory ◽  
The Standard Model ◽  
Meson Mixing ◽  
Additional Anomaly ◽  
Lepton Flavour

Flavour anomalies have attracted a lot of attention over recent years as they provide unique hints for possible New Physics. Here, we consider a supersymmetric (SUSY) extension of the Standard Model (SM) with an additional anomaly-free gauge U(1) group. The key feature of our model is the particular choice of non-universal charges to the gauge boson Z′, which not only allows a relaxation of the flavour discrepancies but, contrary to previous studies, can reproduce the SM mixing matrices both in the quark and lepton sectors. We pay special attention to the latter and explicitly enumerate all parameters relevant for our calculation in the low-energy effective theory. We find regions in the parameter space that satisfy experimental constraints on meson mixing and LHC Z′ searches and can alleviate the flavour anomalies. In addition, we also discuss the predictions for lepton-flavour violating decays B+→K+μτ and B+→K+eτ.

The sircular polarization of γ-quanta in the radiative decay H Þ`ffγ (II)

2021 ◽  
pp. 134-141
Author(s):  
S.K. Abdullayev ◽  
◽  
E.Sh. Omarova ◽  
Keyword(s):  
Higgs Boson ◽  
Standard Model ◽  
Circular Polarization ◽  
Invariant Mass ◽  
Decay Width ◽  
Radiative Decay ◽  
W Boson ◽  
Decay Channel ◽  
Fermion Pair ◽  
The Standard Model

Within the framework of the Standard Model, the radiative decay channel of the Higgs boson into fermion-antifermion pair is investigated: H Þ` ff γ. Taking into account the fermion and W -boson loop diagrams an analytical expression for the decay width is obtained, the circular polarization of the γ-quanta is studied in dependence of the angle θ and invariant mass of the fermion pair.

scholarly journals W-boson production in the high energy electron-photon collisions

2019 ◽  
pp. 41-50
Author(s):  
Ivan A. Shershan ◽  
Tatiana V. Shishkina
Keyword(s):  
Standard Model ◽  
Cross Sections ◽  
W Boson ◽  
High Energy ◽  
New Physics ◽  
Coupling Constants ◽  
Boson Production ◽  
The Standard Model ◽  
Electron Photon ◽  
W Boson Production

In this paper the analysis of W-boson production process in high-energy electron-photon collisions as a tool to search for deviations from the Standard Model is considered. In particular, a set of extended gauge models, including anomalous multi-boson interactions, are discussed as a promising way for «new physics» study. A numerical analysis of the total cross sections of the processes was carried out. The lowest order radiative corrections in the soft-photon approximation within the Standard Model are taken into account. Calculations beyond the Standard Model was performed, the kinematic features of the cross sections were identified. The restrictions on the anomalous triple gauge boson coupling constants were analyzed and the kinematic areas to the search for their manifestations were obtained during the experiments at the International Linear Collider. The paper shows that the search for «new physics» effects based on electron-photon collisions around the W-boson production peak is the maximal promising. It was also shown that future experiments at high luminosity linear colliders will significantly clarify the constraints on anomalous gauge coupling constants.

scholarly journals RARE DECAYS AND CP VIOLATION BEYOND THE STANDARD MODEL

2006 ◽  
Vol 21 (08n09) ◽  
pp. 1738-1749 ◽  
Author(s):  
LUCA SILVESTRINI
Keyword(s):  
Cp Violation ◽  
Standard Model ◽  
Rare Decays ◽  
New Physics ◽  
Beyond The Standard Model ◽  
Unitarity Triangle ◽  
Minimal Flavour Violation ◽  
The Standard Model ◽  
The Status ◽  
Flavour Violation

We review the status of rare decays and CP violation in extensions of the Standard Model. We analyze the determination of the unitarity triangle and the model-independent constraints on new physics that can be derived from this analysis. We find stringent bounds on new contributions to [Formula: see text] and [Formula: see text] mixing, pointing either to models of minimal flavour violation or to models with new sources of flavour and CP violation in b → s transitions. We discuss the status of the universal unitarity triangle in minimal flavour violation, and study rare decays in this class of models. We then turn to supersymmetric models with nontrivial mixing between second and third generation squarks, discuss the present constraints on this mixing and analyze the possible effects on CP violation in b → s nonleptonic decays and on [Formula: see text] mixing. We conclude presenting an outlook on Lepton-Photon 2009.

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