STATUS OF STANDARD MODEL PARAMETERS

2001 ◽  
Vol 16 (supp01a) ◽  
pp. 25-40
Author(s):  
ANTHONY R. BARKER

Recent experimental progress in determining the parameters of the electroweak sector of the Standard Model is summarized. The principal topics addressed include the precision determination of electroweak parameters using LEP and SLD data at the Z0 pole, measurements of the W mass by LEP-II, CDF, and D0, and determination of the elements of the CKM matrix using a variety of experimental methods.

1997 ◽  
Vol 12 (23) ◽  
pp. 4109-4154 ◽  
Author(s):  
Peter B. Renton

The present status of precision electroweak data is reviewed. These data include LEP measurements of the mass and width of the Z, together with various measurements on the Z-fermion couplings. These data are compared to, and combined with, data from the SLC on the left–right polarized asymmetry, A LR , and the left–right forward–backward asymmetries for b and c quarks. These measurements are combined with hadron collider measurements from the Tevatron and CERN on the mass of the W boson, mW, as well as other electroweak data, in global electroweak fits in which various Standard Model parameters are determined. A comparison is made between the results of direct measurements of mW and the top-quark mass, mt, as determined from the Tevatron, with the indirect results coming from electroweak radiative corrections. Using all precision electroweak data, fits are also made to determine limits on the mass of the Higgs boson, mH. The influence on these limits of specific measurements, particularly those which are somewhat inconsistent with the Standard Model, is explored. The data are also analyzed in terms of the quasi model independent ∊ variables. Improvements in the determination of all of these quantities are expected when the Z data at LEP are fully analyzed, and further measurements on A LR and related asymmetries performed at the SLC. In addition, substantial improvements in the determination of mW are expected from measurements at the Tevatron and in the second phase of LEP. An estimate is made of the likely precision of these data, and the implications of the impact of these data on precision electroweak tests are discussed. This discussion is made both in terms of the Standard Model and also in the context of the quasi model independent ∊ variables.


2014 ◽  
Vol 35 ◽  
pp. 1460405 ◽  
Author(s):  
MARC KNECHT

The contributions from the standard model interactions to the anomalous magnetic moments of the two lightest charged leptons, the electron and the muon, are reviewed. Comparison with the very accurately measured experimental values is made, using the most recent high-precision determination of the fine structure constant.


2000 ◽  
Vol 50 (1) ◽  
pp. 249-297 ◽  
Author(s):  
A.R. Barker ◽  
S.H. Kettell

▪ Abstract  We review the current status of the field of rare kaon decays. The study of rare kaon decays has played a key role in the development of the standard model, and the field continues to have significant impact. The two areas of greatest import are the search for physics beyond the standard model and the determination of fundamental standard-model parameters. Due to the exquisite sensitivity of rare kaon decay experiments, searches for new physics can probe very high mass scales. Studies of the K → π ν[Formula: see text] modes in particular, where the first event has recently been seen, will permit tests of the standard-model picture of quark mixing and CP violation.


1990 ◽  
Vol 234 (4) ◽  
pp. 525-533 ◽  
Author(s):  
I. Adachi ◽  
M. Doser ◽  
R. Enomoto ◽  
H. Fujii ◽  
K. Fujii ◽  
...  

2021 ◽  
Vol 2021 (7) ◽  
Author(s):  
Avital Dery ◽  
Mitrajyoti Ghosh ◽  
Yuval Grossman ◽  
Stefan Schacht

Abstract The K → μ+μ− decay is often considered to be uninformative of fundamental theory parameters since the decay is polluted by long-distance hadronic effects. We demonstrate that, using very mild assumptions and utilizing time-dependent interference effects, ℬ(KS → μ+μ−)ℓ=0 can be experimentally determined without the need to separate the ℓ = 0 and ℓ = 1 final states. This quantity is very clean theoretically and can be used to test the Standard Model. In particular, it can be used to extract the CKM matrix element combination $$ \mid {V}_{ts}{V}_{td}\sin \left(\beta +{\beta}_s\right)\mid \approx \mid {A}^2{\lambda}^5\overline{\eta}\mid $$ ∣ V ts V td sin β + β s ∣ ≈ ∣ A 2 λ 5 η ¯ ∣ with hadronic uncertainties below 1%.


2019 ◽  
Vol 69 (1) ◽  
pp. 191-217 ◽  
Author(s):  
Roger D. Carlini ◽  
Willem T.H. van Oers ◽  
Mark L. Pitt ◽  
Gregory R. Smith

This article discusses some of the history of parity-violation experiments that culminated in the Qweak experiment, which provided the first determination of the proton's weak charge [Formula: see text]. The guiding principles necessary to the success of that experiment are outlined, followed by a brief description of the Qweak experiment. Several consistent methods used to determine [Formula: see text] from the asymmetry measured in the Qweak experiment are explained in detail. The weak mixing angle sin2θw determined from [Formula: see text] is compared with results from other experiments. A description of the procedure for using the [Formula: see text] result on the proton to set TeV-scale limits for new parity-violating semileptonic physics beyond the Standard Model (BSM) is presented. By also considering atomic parity-violation results on cesium, the article shows how this result can be generalized to set limits on BSM physics, which couples to any combination of valence quark flavors. Finally, the discovery space available to future weak-charge measurements is explored.


2003 ◽  
Vol 18 (1-4) ◽  
pp. 55-75 ◽  
Author(s):  
C.D. Froggatt* ◽  
H.B. Nielsen†

2000 ◽  
Vol 15 (16) ◽  
pp. 2605-2611 ◽  
Author(s):  
TOMOMI OHGAKI

We demonstrate a measurement of the Higgs boson mass by the method of energy scanning at photon–photon colliders, using the high energy edge of the photon spectrum. With an integrated luminosity of 50 fb-1 it is possible to measure the standard model Higgs mass to within 110 MeV in photon–photon collisions for mh=100 GeV. As for the total width of the Higgs boson, the statistical error ΔΓh/Γh SM=0.06 is expected for mh=100 GeV, if both Γ(h→γγ) and [Formula: see text] are fixed at the predicted standard model value.


2016 ◽  
Vol 206 ◽  
pp. 84-96 ◽  
Author(s):  
Bernd A. Kniehl ◽  
Andrey F. Pikelner ◽  
Oleg L. Veretin

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