相关论文: A Measurement of $R_b$ Using Multiple Tags
The LHCb experiment is one of the four large detectors operating at the LHC at CERN and it is mainly devoted to CP violation measurements and to the search for new physics in rare decays of beauty and charm hadrons. The data from the two…
The re-analysis of the archived data recorded at the ${\rm Z}^{0}$ resonance by the ALEPH experiment at LEP during the years 1992-1995 shows an excess in the opposite sign di-muon mass spectra at 30.40 $\pm$ 0.46 GeV in events containing b…
An extensive sensor testing campaign is presented, dedicated to measuring the charge collection properties of prototype candidates for the Vertex Locator (VELO) detector for the upgraded LHCb experiment. The charge collection is measured…
Based on background measurements at PEP II the impact of machine-related backgrounds on individual components of multipurpose detectors is examined, that operate in an asymmetric B factory at luminosities up to 10^{36} cm^{-2} s^{-1}.…
We report a new measurement of A_b using data obtained by SLD in 1997-98. This measurement uses a vertex tag technique, where the selection of a b hemisphere is based on the reconstructed mass of the bottom hadron decay vertex. The method…
Searches have been conducted for a broad range of new phenomena by the four experiments ALEPH, DELPHI, L3, and OPAL, at LEP2. Each experiment contributes approximately 150 pb-1 of e+e- annihilation data with a mean sqrt(s) of 205.9 GeV in…
Since 1995, LEP has steadily increased the center of mass energy of the colliding beams, from the M_Z resonance to 133, 161 and 172 GeV. New measurements of the strong coupling constant, alpha_s, at these energies have been performed by the…
The goal of the LHCb experiment is the indirect search for New Physics through precision measurements of B-decays. A short description of the detector and its performance after the first data taking in 2009 and 2010 will be presented. In…
Tests of lepton flavour universality in charged-current $B$ decays offer an excellent opportunity to test the Standard Model, and show hints of new physics in analyses performed by the LHCb, Belle and BaBar experiments. These proceedings…
Using the OPAL detector at LEP, the running of the effective QED coupling alpha(t) is measured for space-like momentum transfer from the angular distribution of small-angle Bhabha scattering. In an almost ideal QED framework, with very…
New measurements from ATLAS at the LHC are presented on the total cross section at $\sqrt{s}=8$ TeV from elastic scattering using the ALFA sub-detector and on the inelastic cross section at $\sqrt{s}=13$ TeV using the MBTS sub-detector.
Recently the LHCb collaboration has confirmed the evidence for lepton flavour nonuniversality at the $3.1\sigma$ level via an updated measurement of $R_K$. In this work we analyse this evidence within a model-independent approach. We make…
The calibration and performance of the opposite-side flavour tagging algorithms used for the measurements of time-dependent asymmetries at the LHCb experiment are described. The algorithms have been developed using simulated events and…
The latest preliminary combined results of the Higgs boson searches from the LEP experiments ALEPH, DELPHI, L3 and OPAL are presented. A general scan of the MSSM parameters is performed and leads to stringent lower mass limits and for the…
A small deviation observed around 95 GeV in the diphoton invariant mass distribution in the LHC Run 2 data has been subject to considerable attention in the past couple of years. The interpretation of this excess as the manifestation of an…
We report a new measurement of the CKM parameter V_ub made with a sample of 9.7 million B B-bar events collected with the CLEO II detector. Using Heavy Quark theory, we combine the observed yield of leptons from semileptonic B decay in the…
A total of 628 pb-1 of data collected with the ALEPH detector at centre-of-mass energies from 189 to 209 GeV is analysed in the search for gauge mediated supersymmetry breaking (GMSB) topologies. In this framework, a novel search for…
The lifetimes of the Bbar0 and B- mesons are measured using a sample of about four million hadronic Z decays collected from 1991 to 1995 with the ALEPH detector at LEP. The data sample has been recently reprocessed, achieving a substantial…
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…
This paper describes recent developments in Heavy Flavour physics at LEP, focusing on a new result from the ALEPH Collaboration on the search for flavour oscillations of the Bs meson. The impact of this analysis on the world combination and…