相关论文: $\alpha_s(M_Z^2)$ and $R_b$ discrepancy with nonun…
We find that re-analyzing the LEP/SLC data with light superpartners and low $\alpha_s(\mz^2)\simeq 0.112$ yields a better fit to the data than the Standard Model, giving a satisfactory description of the $R_b$ measurement, and a better fit…
This work is an extension of a previous publication [1] where we fitted the strong coupling $\alpha_s$ together with the non-perturbative parameter $\alpha_0$ from event-shape and jet-shape distributions using power corrections computed in…
We analyze LEP and SLC data from the 1995 Summer Conferences as well as from low energy neutral current experiments for signals of new physics. The reasons for doing this are twofold, first to explain the deviations from the standard model…
The value of $\alpha_s (M_Z)$ emerging from the so called global fits based mainly on the data at the $Z$ peak (and assuming the standard model) is three standard deviations higher than the one stemming from the low-energy phenomenology.…
We analyze LEP and SLC data from the 1995 Winter Conferences for signals of new physics. We compare the data with the Standard Model (SM) as well as a number of test hypotheses concerning the nature of new physics: (i) nonstandard Zbb…
We survey the implications for new physics of the discrepancy between the LEP measurement of $R_b$ and its Standard Model prediction. Two broad classes of models are considered: ($i$) those in which new $Z\bbar b$ couplings arise at tree…
The LHCb experiment has made several measurements in $b \to s$ transitions which indicate tensions with the Standard Model predictions. Assuming the source of these tensions to be new physics, we present new global fits to all Wilson…
Recent results on jet physics and tests of QCD from hadronic final states in $e^+e^-$ annihilation at PETRA and at LEP are reviewed, with special emphasis on hadronic event shapes, charged particle production rates, properties of quark and…
We critically reexamine the precision tests of the standard model by coupling the current world average value of $M_W$ with the recent LEP electroweak data with the aid of a modified ZFITTER program to include the dominant two-loop and…
Tests of lepton-universality as rate ratios in $b\to s \ell\ell$ transitions can be predicted very accurately in the Standard Model. The deficits with respect to expectations reported by the LHCb experiment in muon-to-electron ratios of the…
We explore the nonuniversal interaction effects in terms of the precision variables epsilons with the recent LEP data reported by the Electroweak Working Group. The epsilon variables with the nonuniversal interactions are calculated and…
A set of equations representing the $W/Z$ mass ratio and various observables of $Z$ decays in terms of $\bar\alpha \equiv\alpha (m_Z)$, $G_{\mu}$, $m_Z$, $m_t$, $m_H$, $\bar\alpha_{s} \equiv\alpha_{s} (m_Z)$, $m_b$ and $m_\tau$ (all other…
New results from measurements of the strong coupling constant $\alpha_s(M_Z)$ at LEP are presented. In particular, a new LEP combination of results based on event-shape variables has become available, where a new method for the estimation…
Most recent tests of the Standard Model of the electroweak interaction are reported using data from the four LEP experiments ALEPH, DELPHI, L3 and OPAL, the SLD experiment at SLC, the Tevatron ppbar experiments CDF and D0, and the NuTeV…
We perform a global fit to neutrino oscillation and coherent neutrino-nucleus scattering data, using both timing and energy information from the COHERENT experiment. The results are used to set model-independent bounds on four-fermion…
We discuss the impact of the recent precision measurements at LEP on the minimal supersymmetric standard model. We show that the values of $\tan\beta$ necessary to induce large positive corrections to $R_b$ are the same as the ones…
Depending on the assumptions on the power corrections to the exclusive b -> s l+ l- decays, the latest data of the LHCb collaboration - based on the 3 fb^-1 data set and on two different experimental analysis methods - still shows some…
We use the available data on e+ e- -> hadrons to determine the value of the QED coupling at the Z pole. The inclusion of recent preliminary BES-II data in the analysis is found to reduce the ambiguity in the determination of the coupling,…
Most models for soft interactions which were proposed prior to the measurements at the LHC, are only marginally compatible with LHC data, our GLM model has the same deficiency. In this paper we investigate possible causes of the problem, by…
Recent results of tests of the Standard Model of electroweak interactions are presented. Data are used from the four LEP experiments, ALEPH, DELPHI, L3, OPAL, the SLD experiment at SLC, the TEVATRON p-pbar experiments CDF and D0 and the…